CA2840747A1 - Hybrid materials and nanocomposite materials, methods of making same, and uses thereof - Google Patents
Hybrid materials and nanocomposite materials, methods of making same, and uses thereof Download PDFInfo
- Publication number
- CA2840747A1 CA2840747A1 CA2840747A CA2840747A CA2840747A1 CA 2840747 A1 CA2840747 A1 CA 2840747A1 CA 2840747 A CA2840747 A CA 2840747A CA 2840747 A CA2840747 A CA 2840747A CA 2840747 A1 CA2840747 A1 CA 2840747A1
- Authority
- CA
- Canada
- Prior art keywords
- metal
- nanoparticles
- carbon
- nanocomposite
- nanocomposite material
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000000463 material Substances 0.000 title claims abstract description 183
- 239000002114 nanocomposite Substances 0.000 title claims abstract description 105
- 238000000034 method Methods 0.000 title claims abstract description 80
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 145
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 139
- 239000002105 nanoparticle Substances 0.000 claims abstract description 123
- 229910052751 metal Inorganic materials 0.000 claims abstract description 104
- 239000002184 metal Substances 0.000 claims abstract description 101
- 239000011159 matrix material Substances 0.000 claims abstract description 66
- 239000002243 precursor Substances 0.000 claims abstract description 61
- 150000001875 compounds Chemical class 0.000 claims abstract description 30
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 claims description 62
- 229920000642 polymer Polymers 0.000 claims description 43
- 229910044991 metal oxide Inorganic materials 0.000 claims description 38
- 150000004706 metal oxides Chemical class 0.000 claims description 38
- 229910052961 molybdenite Inorganic materials 0.000 claims description 34
- CWQXQMHSOZUFJS-UHFFFAOYSA-N molybdenum disulfide Chemical compound S=[Mo]=S CWQXQMHSOZUFJS-UHFFFAOYSA-N 0.000 claims description 34
- 229910052982 molybdenum disulfide Inorganic materials 0.000 claims description 34
- 239000000178 monomer Substances 0.000 claims description 32
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 claims description 29
- -1 halide compound Chemical class 0.000 claims description 28
- GHMLBKRAJCXXBS-UHFFFAOYSA-N resorcinol Chemical compound OC1=CC=CC(O)=C1 GHMLBKRAJCXXBS-UHFFFAOYSA-N 0.000 claims description 24
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 20
- 239000011541 reaction mixture Substances 0.000 claims description 17
- MYRTYDVEIRVNKP-UHFFFAOYSA-N 1,2-Divinylbenzene Chemical compound C=CC1=CC=CC=C1C=C MYRTYDVEIRVNKP-UHFFFAOYSA-N 0.000 claims description 15
- 238000010438 heat treatment Methods 0.000 claims description 15
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 claims description 14
- 229910052976 metal sulfide Inorganic materials 0.000 claims description 14
- 229920002239 polyacrylonitrile Polymers 0.000 claims description 13
- NIFIFKQPDTWWGU-UHFFFAOYSA-N pyrite Chemical compound [Fe+2].[S-][S-] NIFIFKQPDTWWGU-UHFFFAOYSA-N 0.000 claims description 13
- 229910005391 FeSn2 Inorganic materials 0.000 claims description 12
- 229910052960 marcasite Inorganic materials 0.000 claims description 11
- 229910001463 metal phosphate Inorganic materials 0.000 claims description 11
- 229910052683 pyrite Inorganic materials 0.000 claims description 11
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 10
- 150000007942 carboxylates Chemical class 0.000 claims description 10
- 229910001507 metal halide Inorganic materials 0.000 claims description 10
- 150000005309 metal halides Chemical class 0.000 claims description 10
- 229920001577 copolymer Polymers 0.000 claims description 9
- 239000002082 metal nanoparticle Substances 0.000 claims description 9
- 229910052718 tin Inorganic materials 0.000 claims description 9
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 8
- 239000002904 solvent Substances 0.000 claims description 8
- 229910019142 PO4 Inorganic materials 0.000 claims description 7
- 239000003999 initiator Substances 0.000 claims description 7
- 229910052717 sulfur Inorganic materials 0.000 claims description 7
- 239000011593 sulfur Substances 0.000 claims description 7
- 239000003638 chemical reducing agent Substances 0.000 claims description 6
- 238000004132 cross linking Methods 0.000 claims description 6
- 239000000839 emulsion Substances 0.000 claims description 6
- 238000005191 phase separation Methods 0.000 claims description 5
- RRHGJUQNOFWUDK-UHFFFAOYSA-N Isoprene Chemical compound CC(=C)C=C RRHGJUQNOFWUDK-UHFFFAOYSA-N 0.000 claims description 4
- 229910052493 LiFePO4 Inorganic materials 0.000 claims description 4
- 239000010452 phosphate Substances 0.000 claims description 4
- 229910021594 Copper(II) fluoride Inorganic materials 0.000 claims description 3
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims description 3
- UBEWDCMIDFGDOO-UHFFFAOYSA-N cobalt(II,III) oxide Inorganic materials [O-2].[O-2].[O-2].[O-2].[Co+2].[Co+3].[Co+3] UBEWDCMIDFGDOO-UHFFFAOYSA-N 0.000 claims description 3
- GWFAVIIMQDUCRA-UHFFFAOYSA-L copper(ii) fluoride Chemical compound [F-].[F-].[Cu+2] GWFAVIIMQDUCRA-UHFFFAOYSA-L 0.000 claims description 3
- AMWRITDGCCNYAT-UHFFFAOYSA-L manganese oxide Inorganic materials [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 claims description 3
- GEYXPJBPASPPLI-UHFFFAOYSA-N manganese(III) oxide Inorganic materials O=[Mn]O[Mn]=O GEYXPJBPASPPLI-UHFFFAOYSA-N 0.000 claims description 3
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 claims description 3
- 239000003960 organic solvent Substances 0.000 claims description 3
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 claims description 2
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims description 2
- IMROMDMJAWUWLK-UHFFFAOYSA-N Ethenol Chemical compound OC=C IMROMDMJAWUWLK-UHFFFAOYSA-N 0.000 claims description 2
- WHNWPMSKXPGLAX-UHFFFAOYSA-N N-Vinyl-2-pyrrolidone Chemical compound C=CN1CCCC1=O WHNWPMSKXPGLAX-UHFFFAOYSA-N 0.000 claims description 2
- 239000003945 anionic surfactant Substances 0.000 claims description 2
- 150000004676 glycans Chemical class 0.000 claims description 2
- 229910052748 manganese Inorganic materials 0.000 claims description 2
- 150000002927 oxygen compounds Chemical class 0.000 claims description 2
- 239000005011 phenolic resin Substances 0.000 claims description 2
- 229920001282 polysaccharide Polymers 0.000 claims description 2
- 239000005017 polysaccharide Substances 0.000 claims description 2
- 150000003464 sulfur compounds Chemical class 0.000 claims description 2
- UKRDPEFKFJNXQM-UHFFFAOYSA-N vinylsilane Chemical compound [SiH3]C=C UKRDPEFKFJNXQM-UHFFFAOYSA-N 0.000 claims description 2
- 229910015645 LiMn Inorganic materials 0.000 claims 1
- 229910015862 LiMn0.75Fe0.25PO4 Inorganic materials 0.000 claims 1
- BERDEBHAJNAUOM-UHFFFAOYSA-N copper(I) oxide Inorganic materials [Cu]O[Cu] BERDEBHAJNAUOM-UHFFFAOYSA-N 0.000 claims 1
- KRFJLUBVMFXRPN-UHFFFAOYSA-N cuprous oxide Chemical compound [O-2].[Cu+].[Cu+] KRFJLUBVMFXRPN-UHFFFAOYSA-N 0.000 claims 1
- 238000000197 pyrolysis Methods 0.000 abstract description 25
- 238000011065 in-situ storage Methods 0.000 abstract description 13
- 239000002131 composite material Substances 0.000 description 92
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 47
- 239000002245 particle Substances 0.000 description 33
- 230000015572 biosynthetic process Effects 0.000 description 32
- 230000001351 cycling effect Effects 0.000 description 32
- 229910052744 lithium Inorganic materials 0.000 description 32
- 238000003917 TEM image Methods 0.000 description 28
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 27
- 238000002441 X-ray diffraction Methods 0.000 description 26
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 24
- 239000000203 mixture Substances 0.000 description 24
- 238000002484 cyclic voltammetry Methods 0.000 description 22
- 238000013459 approach Methods 0.000 description 21
- 238000003786 synthesis reaction Methods 0.000 description 20
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 18
- VASIZKWUTCETSD-UHFFFAOYSA-N manganese(II) oxide Inorganic materials [Mn]=O VASIZKWUTCETSD-UHFFFAOYSA-N 0.000 description 17
- 229910001416 lithium ion Inorganic materials 0.000 description 15
- 239000000047 product Substances 0.000 description 14
- 238000002411 thermogravimetry Methods 0.000 description 13
- 238000006243 chemical reaction Methods 0.000 description 12
- 238000009826 distribution Methods 0.000 description 12
- 229910052742 iron Inorganic materials 0.000 description 12
- 238000006116 polymerization reaction Methods 0.000 description 12
- OZAIFHULBGXAKX-UHFFFAOYSA-N 2-(2-cyanopropan-2-yldiazenyl)-2-methylpropanenitrile Chemical compound N#CC(C)(C)N=NC(C)(C)C#N OZAIFHULBGXAKX-UHFFFAOYSA-N 0.000 description 11
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 11
- 239000011149 active material Substances 0.000 description 11
- 229910003481 amorphous carbon Inorganic materials 0.000 description 11
- 238000011066 ex-situ storage Methods 0.000 description 11
- 238000006138 lithiation reaction Methods 0.000 description 11
- 239000011148 porous material Substances 0.000 description 11
- 230000008569 process Effects 0.000 description 11
- 238000003763 carbonization Methods 0.000 description 10
- 238000003780 insertion Methods 0.000 description 10
- 239000000126 substance Substances 0.000 description 10
- 229910002092 carbon dioxide Inorganic materials 0.000 description 9
- 239000003792 electrolyte Substances 0.000 description 9
- 230000037431 insertion Effects 0.000 description 9
- 239000010410 layer Substances 0.000 description 9
- 239000002086 nanomaterial Substances 0.000 description 9
- 235000002639 sodium chloride Nutrition 0.000 description 9
- 230000002776 aggregation Effects 0.000 description 8
- 239000010405 anode material Substances 0.000 description 8
- 239000012298 atmosphere Substances 0.000 description 8
- 239000006229 carbon black Substances 0.000 description 8
- 239000007789 gas Substances 0.000 description 8
- GDTUKPPWQPWALU-UHFFFAOYSA-L iron(2+);undec-10-enoate Chemical compound [Fe+2].[O-]C(=O)CCCCCCCCC=C.[O-]C(=O)CCCCCCCCC=C GDTUKPPWQPWALU-UHFFFAOYSA-L 0.000 description 8
- 230000009467 reduction Effects 0.000 description 8
- 239000001569 carbon dioxide Substances 0.000 description 7
- 239000007772 electrode material Substances 0.000 description 7
- 229910002804 graphite Inorganic materials 0.000 description 7
- 239000010439 graphite Substances 0.000 description 7
- 239000002135 nanosheet Substances 0.000 description 7
- 239000012071 phase Substances 0.000 description 7
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 7
- 239000000843 powder Substances 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- ZFBLAZDACWORER-UHFFFAOYSA-K C(CCCCCCCCC=C)(=O)[O-].[Fe+3].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-] Chemical compound C(CCCCCCCCC=C)(=O)[O-].[Fe+3].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-] ZFBLAZDACWORER-UHFFFAOYSA-K 0.000 description 6
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 6
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 6
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 description 6
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 6
- 238000004220 aggregation Methods 0.000 description 6
- 238000001027 hydrothermal synthesis Methods 0.000 description 6
- 238000010348 incorporation Methods 0.000 description 6
- 238000009830 intercalation Methods 0.000 description 6
- 230000002687 intercalation Effects 0.000 description 6
- 150000002739 metals Chemical class 0.000 description 6
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 6
- 150000003839 salts Chemical class 0.000 description 6
- 238000003860 storage Methods 0.000 description 6
- XOJVVFBFDXDTEG-UHFFFAOYSA-N Norphytane Natural products CC(C)CCCC(C)CCCC(C)CCCC(C)C XOJVVFBFDXDTEG-UHFFFAOYSA-N 0.000 description 5
- 230000014759 maintenance of location Effects 0.000 description 5
- 239000011572 manganese Substances 0.000 description 5
- GTQVWDVXPMDLMZ-UHFFFAOYSA-L manganese(2+);undec-10-enoate Chemical compound [Mn+2].[O-]C(=O)CCCCCCCCC=C.[O-]C(=O)CCCCCCCCC=C GTQVWDVXPMDLMZ-UHFFFAOYSA-L 0.000 description 5
- 230000003647 oxidation Effects 0.000 description 5
- 238000007254 oxidation reaction Methods 0.000 description 5
- 230000001590 oxidative effect Effects 0.000 description 5
- 229910052700 potassium Inorganic materials 0.000 description 5
- 229910052708 sodium Inorganic materials 0.000 description 5
- 239000011734 sodium Substances 0.000 description 5
- 239000004094 surface-active agent Substances 0.000 description 5
- 230000002194 synthesizing effect Effects 0.000 description 5
- 229910000314 transition metal oxide Inorganic materials 0.000 description 5
- 238000011282 treatment Methods 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 229910009735 Li2FeS2 Inorganic materials 0.000 description 4
- 239000002033 PVDF binder Substances 0.000 description 4
- 238000001237 Raman spectrum Methods 0.000 description 4
- 125000000217 alkyl group Chemical group 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 4
- 238000001354 calcination Methods 0.000 description 4
- 150000001721 carbon Chemical class 0.000 description 4
- 238000012512 characterization method Methods 0.000 description 4
- 239000013078 crystal Substances 0.000 description 4
- ZKKLPDLKUGTPME-UHFFFAOYSA-N diazanium;bis(sulfanylidene)molybdenum;sulfanide Chemical compound [NH4+].[NH4+].[SH-].[SH-].S=[Mo]=S ZKKLPDLKUGTPME-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000007720 emulsion polymerization reaction Methods 0.000 description 4
- 238000005087 graphitization Methods 0.000 description 4
- 238000011068 loading method Methods 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 238000001878 scanning electron micrograph Methods 0.000 description 4
- 230000006641 stabilisation Effects 0.000 description 4
- 238000011105 stabilization Methods 0.000 description 4
- DCPQMMXBQHAGJZ-UHFFFAOYSA-J C(CCCCCCCCC=C)(=O)[O-].[Sn+4].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-] Chemical compound C(CCCCCCCCC=C)(=O)[O-].[Sn+4].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-] DCPQMMXBQHAGJZ-UHFFFAOYSA-J 0.000 description 3
- 229910002483 Cu Ka Inorganic materials 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- 229910001290 LiPF6 Inorganic materials 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- 238000005275 alloying Methods 0.000 description 3
- 239000008346 aqueous phase Substances 0.000 description 3
- 239000012300 argon atmosphere Substances 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000011852 carbon nanoparticle Substances 0.000 description 3
- 150000001734 carboxylic acid salts Chemical class 0.000 description 3
- 238000005119 centrifugation Methods 0.000 description 3
- 238000007334 copolymerization reaction Methods 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 229920006037 cross link polymer Polymers 0.000 description 3
- 238000002848 electrochemical method Methods 0.000 description 3
- 238000002149 energy-dispersive X-ray emission spectroscopy Methods 0.000 description 3
- 239000000499 gel Substances 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 229910001512 metal fluoride Inorganic materials 0.000 description 3
- 229910001092 metal group alloy Inorganic materials 0.000 description 3
- 239000012299 nitrogen atmosphere Substances 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 235000021317 phosphate Nutrition 0.000 description 3
- 230000002441 reversible effect Effects 0.000 description 3
- 238000007086 side reaction Methods 0.000 description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 description 3
- 239000011780 sodium chloride Substances 0.000 description 3
- 238000000527 sonication Methods 0.000 description 3
- 238000001179 sorption measurement Methods 0.000 description 3
- 239000007858 starting material Substances 0.000 description 3
- 229910052720 vanadium Inorganic materials 0.000 description 3
- DGXAGETVRDOQFP-UHFFFAOYSA-N 2,6-dihydroxybenzaldehyde Chemical compound OC1=CC=CC(O)=C1C=O DGXAGETVRDOQFP-UHFFFAOYSA-N 0.000 description 2
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 description 2
- YIXIQULKJFCNOQ-UHFFFAOYSA-I C(CCCCCCCCC=C)(=O)[O-].[V+5].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-] Chemical compound C(CCCCCCCCC=C)(=O)[O-].[V+5].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-].C(CCCCCCCCC=C)(=O)[O-] YIXIQULKJFCNOQ-UHFFFAOYSA-I 0.000 description 2
- 101100457021 Caenorhabditis elegans mag-1 gene Proteins 0.000 description 2
- 239000006245 Carbon black Super-P Substances 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 229910016043 LixMoS2 Inorganic materials 0.000 description 2
- 101100067996 Mus musculus Gbp1 gene Proteins 0.000 description 2
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000004743 Polypropylene Substances 0.000 description 2
- 229910001128 Sn alloy Inorganic materials 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 229940024606 amino acid Drugs 0.000 description 2
- 150000001413 amino acids Chemical class 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 239000011203 carbon fibre reinforced carbon Substances 0.000 description 2
- 239000007833 carbon precursor Substances 0.000 description 2
- 239000010406 cathode material Substances 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 239000011889 copper foil Substances 0.000 description 2
- 125000004122 cyclic group Chemical group 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 description 2
- 238000003487 electrochemical reaction Methods 0.000 description 2
- 238000000724 energy-dispersive X-ray spectrum Methods 0.000 description 2
- 238000011049 filling Methods 0.000 description 2
- 239000011888 foil Substances 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 229910052595 hematite Inorganic materials 0.000 description 2
- 239000011019 hematite Substances 0.000 description 2
- 239000007970 homogeneous dispersion Substances 0.000 description 2
- 238000010335 hydrothermal treatment Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000001802 infusion Methods 0.000 description 2
- AQBLLJNPHDIAPN-LNTINUHCSA-K iron(3+);(z)-4-oxopent-2-en-2-olate Chemical compound [Fe+3].C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O AQBLLJNPHDIAPN-LNTINUHCSA-K 0.000 description 2
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- 150000002902 organometallic compounds Chemical class 0.000 description 2
- 235000011007 phosphoric acid Nutrition 0.000 description 2
- 229920005596 polymer binder Polymers 0.000 description 2
- 239000002491 polymer binding agent Substances 0.000 description 2
- 229920001155 polypropylene Polymers 0.000 description 2
- 238000002459 porosimetry Methods 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 238000010526 radical polymerization reaction Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
- 238000007669 thermal treatment Methods 0.000 description 2
- 238000004627 transmission electron microscopy Methods 0.000 description 2
- 238000001106 transmission high energy electron diffraction data Methods 0.000 description 2
- GPPXJZIENCGNKB-UHFFFAOYSA-N vanadium Chemical compound [V]#[V] GPPXJZIENCGNKB-UHFFFAOYSA-N 0.000 description 2
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 2
- KKPUODLFBBWJPH-DKWTVANSSA-L (2s)-2-aminobutanedioate;iron(2+) Chemical compound [Fe+2].[O-]C(=O)[C@@H](N)CC([O-])=O KKPUODLFBBWJPH-DKWTVANSSA-L 0.000 description 1
- FRPZMMHWLSIFAZ-UHFFFAOYSA-N 10-undecenoic acid Chemical compound OC(=O)CCCCCCCCC=C FRPZMMHWLSIFAZ-UHFFFAOYSA-N 0.000 description 1
- OWEGMIWEEQEYGQ-UHFFFAOYSA-N 100676-05-9 Natural products OC1C(O)C(O)C(CO)OC1OCC1C(O)C(O)C(O)C(OC2C(OC(O)C(O)C2O)CO)O1 OWEGMIWEEQEYGQ-UHFFFAOYSA-N 0.000 description 1
- YAAYJRKCGZQWCB-UHFFFAOYSA-N 2-(1-cyanopropyldiazenyl)butanenitrile Chemical compound CCC(C#N)N=NC(CC)C#N YAAYJRKCGZQWCB-UHFFFAOYSA-N 0.000 description 1
- XMNIXWIUMCBBBL-UHFFFAOYSA-N 2-(2-phenylpropan-2-ylperoxy)propan-2-ylbenzene Chemical compound C=1C=CC=CC=1C(C)(C)OOC(C)(C)C1=CC=CC=C1 XMNIXWIUMCBBBL-UHFFFAOYSA-N 0.000 description 1
- OAVRWNUUOUXDFH-UHFFFAOYSA-H 2-hydroxypropane-1,2,3-tricarboxylate;manganese(2+) Chemical compound [Mn+2].[Mn+2].[Mn+2].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O OAVRWNUUOUXDFH-UHFFFAOYSA-H 0.000 description 1
- CQMNNMLVXSWLCH-UHFFFAOYSA-B 2-hydroxypropane-1,2,3-tricarboxylate;tin(4+) Chemical compound [Sn+4].[Sn+4].[Sn+4].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O CQMNNMLVXSWLCH-UHFFFAOYSA-B 0.000 description 1
- VFXXTYGQYWRHJP-UHFFFAOYSA-N 4,4'-azobis(4-cyanopentanoic acid) Chemical compound OC(=O)CCC(C)(C#N)N=NC(C)(CCC(O)=O)C#N VFXXTYGQYWRHJP-UHFFFAOYSA-N 0.000 description 1
- RZVAJINKPMORJF-UHFFFAOYSA-N Acetaminophen Chemical compound CC(=O)NC1=CC=C(O)C=C1 RZVAJINKPMORJF-UHFFFAOYSA-N 0.000 description 1
- QYEXBYZXHDUPRC-UHFFFAOYSA-N B#[Ti]#B Chemical compound B#[Ti]#B QYEXBYZXHDUPRC-UHFFFAOYSA-N 0.000 description 1
- 238000004438 BET method Methods 0.000 description 1
- 239000004342 Benzoyl peroxide Substances 0.000 description 1
- OMPJBNCRMGITSC-UHFFFAOYSA-N Benzoylperoxide Chemical compound C=1C=CC=CC=1C(=O)OOC(=O)C1=CC=CC=C1 OMPJBNCRMGITSC-UHFFFAOYSA-N 0.000 description 1
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical compound [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 description 1
- 239000004971 Cross linker Substances 0.000 description 1
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 1
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 description 1
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- 239000012692 Fe precursor Substances 0.000 description 1
- 229910015400 FeC13 Inorganic materials 0.000 description 1
- 229910005432 FeSx Inorganic materials 0.000 description 1
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 1
- 238000001157 Fourier transform infrared spectrum Methods 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 239000002211 L-ascorbic acid Substances 0.000 description 1
- 235000000069 L-ascorbic acid Nutrition 0.000 description 1
- 229910008365 Li-Sn Inorganic materials 0.000 description 1
- 229910006759 Li—Sn Inorganic materials 0.000 description 1
- GUBGYTABKSRVRQ-PICCSMPSSA-N Maltose Natural products O[C@@H]1[C@@H](O)[C@H](O)[C@@H](CO)O[C@@H]1O[C@@H]1[C@@H](CO)OC(O)[C@H](O)[C@H]1O GUBGYTABKSRVRQ-PICCSMPSSA-N 0.000 description 1
- 239000012697 Mn precursor Substances 0.000 description 1
- 229910016003 MoS3 Inorganic materials 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- VSOYJNRFGMJBAV-UHFFFAOYSA-N N.[Mo+4] Chemical compound N.[Mo+4] VSOYJNRFGMJBAV-UHFFFAOYSA-N 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 239000004734 Polyphenylene sulfide Substances 0.000 description 1
- 238000001069 Raman spectroscopy Methods 0.000 description 1
- 229910008066 SnC12 Inorganic materials 0.000 description 1
- 229910033181 TiB2 Inorganic materials 0.000 description 1
- 229910003092 TiS2 Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- PBNNHBMLMRHZQR-UHFFFAOYSA-A [V+5].[V+5].[V+5].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O Chemical compound [V+5].[V+5].[V+5].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O.[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O PBNNHBMLMRHZQR-UHFFFAOYSA-A 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- WQZGKKKJIJFFOK-PHYPRBDBSA-N alpha-D-galactose Chemical compound OC[C@H]1O[C@H](O)[C@H](O)[C@@H](O)[C@H]1O WQZGKKKJIJFFOK-PHYPRBDBSA-N 0.000 description 1
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 239000012736 aqueous medium Substances 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 229960005070 ascorbic acid Drugs 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 235000019400 benzoyl peroxide Nutrition 0.000 description 1
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 1
- GUBGYTABKSRVRQ-QUYVBRFLSA-N beta-maltose Chemical compound OC[C@H]1O[C@H](O[C@H]2[C@H](O)[C@@H](O)[C@H](O)O[C@@H]2CO)[C@H](O)[C@@H](O)[C@@H]1O GUBGYTABKSRVRQ-QUYVBRFLSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000003139 buffering effect Effects 0.000 description 1
- KHAVLLBUVKBTBG-UHFFFAOYSA-N caproleic acid Natural products OC(=O)CCCCCCCC=C KHAVLLBUVKBTBG-UHFFFAOYSA-N 0.000 description 1
- 239000002717 carbon nanostructure Substances 0.000 description 1
- 239000003575 carbonaceous material Substances 0.000 description 1
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 150000001860 citric acid derivatives Chemical class 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 239000003431 cross linking reagent Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 238000000445 field-emission scanning electron microscopy Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 229930182830 galactose Natural products 0.000 description 1
- 229910052732 germanium Inorganic materials 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- JYVHOGDBFNJNMR-UHFFFAOYSA-N hexane;hydrate Chemical compound O.CCCCCC JYVHOGDBFNJNMR-UHFFFAOYSA-N 0.000 description 1
- 239000008240 homogeneous mixture Substances 0.000 description 1
- 239000012456 homogeneous solution Substances 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 238000010952 in-situ formation Methods 0.000 description 1
- 238000002065 inelastic X-ray scattering Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- 235000013980 iron oxide Nutrition 0.000 description 1
- NNIPDXPTJYIMKW-UHFFFAOYSA-N iron tin Chemical compound [Fe].[Sn] NNIPDXPTJYIMKW-UHFFFAOYSA-N 0.000 description 1
- HOIQWTMREPWSJY-GNOQXXQHSA-K iron(3+);(z)-octadec-9-enoate Chemical compound [Fe+3].CCCCCCCC\C=C/CCCCCCCC([O-])=O.CCCCCCCC\C=C/CCCCCCCC([O-])=O.CCCCCCCC\C=C/CCCCCCCC([O-])=O HOIQWTMREPWSJY-GNOQXXQHSA-K 0.000 description 1
- NPFOYSMITVOQOS-UHFFFAOYSA-K iron(III) citrate Chemical compound [Fe+3].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NPFOYSMITVOQOS-UHFFFAOYSA-K 0.000 description 1
- FZGIHSNZYGFUGM-UHFFFAOYSA-L iron(ii) fluoride Chemical compound [F-].[F-].[Fe+2] FZGIHSNZYGFUGM-UHFFFAOYSA-L 0.000 description 1
- SHXXPRJOPFJRHA-UHFFFAOYSA-K iron(iii) fluoride Chemical compound F[Fe](F)F SHXXPRJOPFJRHA-UHFFFAOYSA-K 0.000 description 1
- QDUZQOIJXPPTLY-IYEMJOQQSA-N iron;(2r,3s,4r,5r)-2,3,4,5,6-pentahydroxyhexanoic acid Chemical compound [Fe].OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O.OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O QDUZQOIJXPPTLY-IYEMJOQQSA-N 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 239000003446 ligand Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- WMFOQBRAJBCJND-UHFFFAOYSA-M lithium hydroxide Inorganic materials [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 description 1
- 229910021450 lithium metal oxide Inorganic materials 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 239000011564 manganese citrate Substances 0.000 description 1
- 235000014872 manganese citrate Nutrition 0.000 description 1
- 229940097206 manganese citrate Drugs 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 239000012702 metal oxide precursor Substances 0.000 description 1
- 239000000693 micelle Substances 0.000 description 1
- 229910003455 mixed metal oxide Inorganic materials 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- TVWWSIKTCILRBF-UHFFFAOYSA-N molybdenum trisulfide Chemical compound S=[Mo](=S)=S TVWWSIKTCILRBF-UHFFFAOYSA-N 0.000 description 1
- 230000000877 morphologic effect Effects 0.000 description 1
- 230000004660 morphological change Effects 0.000 description 1
- 238000003541 multi-stage reaction Methods 0.000 description 1
- 229940031182 nanoparticles iron oxide Drugs 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 1
- 238000000696 nitrogen adsorption--desorption isotherm Methods 0.000 description 1
- 239000012454 non-polar solvent Substances 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- 238000005580 one pot reaction Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- 230000037361 pathway Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 229920000553 poly(phenylenevinylene) Polymers 0.000 description 1
- 229920001197 polyacetylene Polymers 0.000 description 1
- 238000006068 polycondensation reaction Methods 0.000 description 1
- 239000013047 polymeric layer Substances 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
- 229920000069 polyphenylene sulfide Polymers 0.000 description 1
- 229920000128 polypyrrole Polymers 0.000 description 1
- 229920000136 polysorbate Polymers 0.000 description 1
- 229940068965 polysorbates Drugs 0.000 description 1
- 229920000123 polythiophene Polymers 0.000 description 1
- USHAGKDGDHPEEY-UHFFFAOYSA-L potassium persulfate Chemical compound [K+].[K+].[O-]S(=O)(=O)OOS([O-])(=O)=O USHAGKDGDHPEEY-UHFFFAOYSA-L 0.000 description 1
- 238000000634 powder X-ray diffraction Methods 0.000 description 1
- 238000001144 powder X-ray diffraction data Methods 0.000 description 1
- 239000005297 pyrex Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000007870 radical polymerization initiator Substances 0.000 description 1
- 230000001172 regenerating effect Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000010963 scalable process Methods 0.000 description 1
- 238000013341 scale-up Methods 0.000 description 1
- 238000004626 scanning electron microscopy Methods 0.000 description 1
- 238000000851 scanning transmission electron micrograph Methods 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000004729 solvothermal method Methods 0.000 description 1
- 238000002336 sorption--desorption measurement Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 150000004763 sulfides Chemical class 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000001757 thermogravimetry curve Methods 0.000 description 1
- 125000000101 thioether group Chemical group 0.000 description 1
- 150000007944 thiolates Chemical class 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229960002703 undecylenic acid Drugs 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 230000004580 weight loss Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G39/00—Compounds of molybdenum
- C01G39/06—Sulfides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82B—NANOSTRUCTURES FORMED BY MANIPULATION OF INDIVIDUAL ATOMS, MOLECULES, OR LIMITED COLLECTIONS OF ATOMS OR MOLECULES AS DISCRETE UNITS; MANUFACTURE OR TREATMENT THEREOF
- B82B3/00—Manufacture or treatment of nanostructures by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82B—NANOSTRUCTURES FORMED BY MANIPULATION OF INDIVIDUAL ATOMS, MOLECULES, OR LIMITED COLLECTIONS OF ATOMS OR MOLECULES AS DISCRETE UNITS; MANUFACTURE OR TREATMENT THEREOF
- B82B1/00—Nanostructures formed by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/45—Phosphates containing plural metal, or metal and ammonium
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G1/00—Methods of preparing compounds of metals not covered by subclasses C01B, C01C, C01D, or C01F, in general
- C01G1/02—Oxides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G1/00—Methods of preparing compounds of metals not covered by subclasses C01B, C01C, C01D, or C01F, in general
- C01G1/12—Sulfides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G19/00—Compounds of tin
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G45/00—Compounds of manganese
- C01G45/02—Oxides; Hydroxides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/02—Oxides; Hydroxides
- C01G49/06—Ferric oxide [Fe2O3]
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/02—Oxides; Hydroxides
- C01G49/08—Ferroso-ferric oxide [Fe3O4]
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
- C01P2002/82—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by IR- or Raman-data
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
- C01P2002/85—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by XPS, EDX or EDAX data
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
- C01P2002/88—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by thermal analysis data, e.g. TGA, DTA, DSC
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/04—Particle morphology depicted by an image obtained by TEM, STEM, STM or AFM
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/16—Pore diameter
- C01P2006/17—Pore diameter distribution
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Nanotechnology (AREA)
- Manufacturing & Machinery (AREA)
- Battery Electrode And Active Subsutance (AREA)
- Carbon And Carbon Compounds (AREA)
- Polymerisation Methods In General (AREA)
- Secondary Cells (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Manufacture Of Alloys Or Alloy Compounds (AREA)
Abstract
Hybrid materials and nanocomposite materials, methods of making and using such materials. The nanoparticles of the nanocomposite are formed in situ during pyrolysis of a hybrid material comprising metal precursor compounds. The nanoparticles are uniformly distributed in the carbon matrix of the nanocomposite. The nanocomposite materials can be used in devices such as, for example, electrodes and on-chip inductors.
Description
HYBRID MATERIALS AND NANOCOMPOSITE MATERIALS, METHODS OF
MAKING SAME, AND USES THEREOF
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional patent application nos.
61/503,085, filed June 30, 2011, and 61/578,464, filed December 21, 2011, the disclosures of which are incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
MAKING SAME, AND USES THEREOF
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional patent application nos.
61/503,085, filed June 30, 2011, and 61/578,464, filed December 21, 2011, the disclosures of which are incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] This invention was made with government support under contract no. DE-SC0001086 awarded by the Department of Energy. The government has certain rights in the invention.
FIELD OF THE INVENTION
FIELD OF THE INVENTION
[0003] The present invention generally relates to composite materials and methods of making such composite materials. More particularly, the present invention relates to in situ formation of nanoparticles embedded in a carbon matrix.
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION
[0004] Rising energy prices and unmet demand for secondary batteries with higher energy & power densities, higher operating voltages, improved cycling stability, enhanced safety, and lower initial and life cycle costs has increased interest in lithium ion batteries (LIB). LIBs demonstrate higher energy density, higher operating voltage and lower self-discharge rates compared to conventional rechargeable batteries. They have consequently received intense scientific and commercial interest for portable electronics applications since the early 1990s. In recent years, the demand for secondary (rechargeable) batteries with better performance, higher charge-rate capability, improved cycling stability, and enhanced safety has steadily increased to meet new needs for smaller, lighter, more powerful electronic devices, as well as to accommodate growing interests in hybrid electric and plug-in hybrid electric vehicles.
[0005] A crucial performance criterion is the cyclability of the electrode materials and a key issue in capacity retention lies in the large structural and morphological changes many electrode materials undergo during cyclic insertion and deinsertion of lithium. Significantly, these changes occur in materials following rather different lithiation mechanisms, including alloying, conversion, and intercalation; implying that general solutions are required. Despite
6 current LIB platforms based on a graphite anode and a lithium metal oxide (e.g., LiC002) cathode is believed to be close to its limits due to the limited gravimetric capacity and rate capability of graphitic carbon as the anode material.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention provides hybrid materials, nanocomposite materials, methods of making such materials. Also provided are uses of such materials.
The hybrid/in situ approach of the instant invention provides homogeneous dispersion of the metal precursor in the polymer matrix (e.g., a cross-linked polymer matrix).
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention provides hybrid materials, nanocomposite materials, methods of making such materials. Also provided are uses of such materials.
The hybrid/in situ approach of the instant invention provides homogeneous dispersion of the metal precursor in the polymer matrix (e.g., a cross-linked polymer matrix).
[0007] In an aspect, the present invention provides a hybrid material. The hybrid material is a polymer comprising a metal precursor. The metal precursor is chemically bonded to the polymer. During pyrolysis of the hybrid material, nanoparticles are formed from the metal precursors. In an embodiment, the step of pyrolysing the hybrid material is carried out such that a nanocomposite material comprising a plurality of nanoparticles, the nanoparticles being formed from the metal component of the one or more metal precursor compounds, embedded in a carbon matrix is formed.
[0008] In an aspect, the present invention provides a nanocomposite material. The nanocomposite material has nanoparticles (e.g., metal nanoparticles, metal oxide nanoparticles, metal halide (e.g., metal fluoride) nanoparticles, metal boride nanoparticles, metal phosphate nanoparticles) embedded in a continuous phase of carbon (i.e., a carbon matrix).
[0009] In an aspect, the present invention provides methods of forming a material.
The material can be a hybrid material or nanocomposite material as described herein.
The material can be a hybrid material or nanocomposite material as described herein.
[0010] In an embodiment, the method for forming a material comprises the steps of:
contacting one or more monomers, one or more metal precursor compounds, optionally, an initiator, and, optionally, one or more solvents to form a reaction mixture, heating the reaction mixture such that a hybrid material comprising a plurality of metal precursor compounds chemically bonded to the polymer matrix is formed and, optionally, isolating the hybrid material. In an embodiment, the method further comprises the step of pyrolysing the hybrid material, such that a nanocomposite material comprising a plurality of metal oxide nanoparticles (or metal nanoparticles) embedded in a carbon matrix is formed.
contacting one or more monomers, one or more metal precursor compounds, optionally, an initiator, and, optionally, one or more solvents to form a reaction mixture, heating the reaction mixture such that a hybrid material comprising a plurality of metal precursor compounds chemically bonded to the polymer matrix is formed and, optionally, isolating the hybrid material. In an embodiment, the method further comprises the step of pyrolysing the hybrid material, such that a nanocomposite material comprising a plurality of metal oxide nanoparticles (or metal nanoparticles) embedded in a carbon matrix is formed.
[0011] In various embodiments, the nanocomposite material is subjected to various ex situ treatments such that nanoparticles of the resulting nanocomposite have different chemical reacted such that metal, metal halide, metal sulfide, and metal phosphate nanoparticles are formed or metal sulfide nanoparticles are reacted such that metal oxides, metal halide, metal, or metal phosphate nanoparticles are formed.
[0012] In an aspect, the present invention provides devices comprising the hybrid material or nanocomposite materials described herein. Examples of such devices include batteries (e.g., secondary batteries), on-chip inductors.
BRIEF DESCRIPTION OF THE FIGURES
BRIEF DESCRIPTION OF THE FIGURES
[0013] Figure 1. An example of an in situ synthesis scheme for Fe304¨C
nanocomposite.
nanocomposite.
[0014] Figure 2. Representative XRD pattern for the Fe304¨C composite created by pyrolysing the as-prepared PAN¨Fe(undec)3 complex.
[0015] Figure 3. Examples of (a) Morphology of polymer¨iron complex;
(b) morphology of Fe304¨C composite; (c) EDS spectrum for the polymer¨iron complex; and (d) TGA data for the Fe304¨C composite.
(b) morphology of Fe304¨C composite; (c) EDS spectrum for the polymer¨iron complex; and (d) TGA data for the Fe304¨C composite.
[0016] Figure 4. Representative Raman spectrum for the Fe304¨C
composite, deconvoluted into peaks for graphitic carbon, disordered graphite lattices and amorphous carbon.
composite, deconvoluted into peaks for graphitic carbon, disordered graphite lattices and amorphous carbon.
[0017] Figure 5. Representative cyclic voltammograms and voltage¨capacity profiles for Fe304¨C nanocomposites.
[0018] Figure 6. Representative cycling performance for (a) Fe304¨C
composites run at 1 C (924 mA h g-1); (b) composite run at 0.2 C; (c) composite run at charging rates; (d) bare Fe304 nanoparticles run at 1 C; and (e) bare carbon made from pyrolysis of PAN¨DVB
run at 1 C.
composites run at 1 C (924 mA h g-1); (b) composite run at 0.2 C; (c) composite run at charging rates; (d) bare Fe304 nanoparticles run at 1 C; and (e) bare carbon made from pyrolysis of PAN¨DVB
run at 1 C.
[0019] Figure 7. Representative nitrogen adsorption isotherms and pore size distribution for the Fe304¨C composite.
[0020] Figure 8. Representative (a) X-Ray diffractogram and (b) TEM
image for MnO¨C composite.
image for MnO¨C composite.
[0021] Figure 9. Representative (a) cyclic voltammograms, (b) voltage¨capacity profiles of MnO¨C composite and (c) cycling performance of MnO¨C composite at 1 C (755 mA h g-1), 0.2 C and at varied charging rates, and cycling performance of pure MnO.
nanoparticles of the following phases: Fe, Fe304, Fe203, MnO, Mn304, Sn, Co, Co304, Cu, Cu0; an example of a TEM image of Cu@C composite.
[0023] Figure 11. Representative XRD patterns of nanocomposites embedding the nanoparticles of the following phases: Ti02(anatase), V205, ZnO, Zr02; an example of a TEM image of Ti02@C composite.
[0024] Figure 12. Scheme for synthesizing Co@C and CoS@C
nanocomposites;
representative XRD patterns of Co@C and CoS@C nanocomposites.
[0025] Figure 13. Representative XRD pattern for Fe304@C and LiFePO4@C
nanocomposites.
[0026] Figure 14. Representative TEM image for LiFePO4@C
nanocomposites.
[0027] Figure 15. Representative XRD pattern for Mn075Fe0250@C and LiMno 75Feo 25PO4@ C nanocomposites.
[0028] Figure 16. Representative TEM image for Mn075Fe0250@C
nanocomposite.
[0029] Figure 17. Representative TEM image for LiMn075Fe025PO4@C
nanocomposite.
[0030] Figure 18. Representative scanning electron micrographs of (a) MS-22, (d) MS-0; transmission electron micrographs of (b and c) MS-22, (e and MS-0;
insets of (b) shows Mo52 nanosheet; SAED patterns of MS-22 and MS-0 in the insets of (c) and (0 respectively.
[0031] Figure 19. An example of a schematic of the synthesis of (A) Mo52¨carbon nanostructure and (B) pure Mo52.
[0032] Figure 20. Representative galvanostatic charge¨discharge curves of (a) MS-0 and (b) MS-22 at a current density of 100 mA g-1; cyclic voltammetry (CV) curves of (c) MS-0 and (d) MS-22 at a scan rate of 0.2 mV 5-1; (e) cycling stability of pure Mo52 and various Mo52¨carbon composites; (f) variation of discharge capacity as a function of carbon weight fraction.
[0033] Figure 21. Representative Ex situ X-ray diffraction patterns of (a) Mo52¨
carbon (22 wt%) composite and (b) pure Mo52 after 1st discharge cycle. Peaks marked by *
corresponds to Cu current collector; scanning electron micrographs of 1st cycle discharged product of (c) MS-22 and (d) MS-0.
50% carbon black in the electrode composition at various current rates in the range of 0.4-4 A g-1.
[0035] Figure 23. Representative X-ray diffraction patterns of pure MoS2 and MoS2-carbon (22 wt %) composite.
[0036] Figure 24. Representative thermogravimetry analysis of pure MoS2, MS-11, MS-22, MS32 and MS-41.
[0037] Figure 25. Representative (a) N2 adsorption/desorption isotherms and (b) pore size distribution of pure MoS2, MS-22 and MS-41.
[0038] Figure 26. Representative transmission electron micrographs of (a) MS-11 and (b) MS-32.
[0039] Figure 27. (a) Representative cycling stability of pure MS-22 with 0%, 10%, 25% and 50% carbon black in the electrode at a current rate of (a) 100 mAg-1;
(b) at various current rates in the range of 0.4-4 Ag-1.
[0040] Figure 28. Representative cycling stability of 550 C and 700 C
calcined Mo52-carbon (22 wt %) composite at a current rate of (a) 100 mAg-1; (b) at various current rates in the range of 0.4-4 Ag-1.
[0041] Figure 29. Representative SAED patterns of (a) pure Mo52 and (b) Mo52-carbon (22 wt %) composite.
[0042] Figure 30. An example of a schematic of synthesis process for creating organic-inorganic copolymer hybrids.
[0043] Figure 31. Representative TEM images of Fe304@C nanocomposite (A) before cycling and (B) after 100 charge-discharge cycles.
[0044] Figure 32. An example of an overview of the platform for synthesizing nanocomposites with embedded structures involving different classes of materials.
[0045] Figure 33. Representative powder XRD patterns (A), TEM images for Fe@C
(B) and Fe52@C (C) composites and size distribution histograms for Fe@C (D) and Fe52@C
(E).
[0046] Figure 34. Representative (A) Cyclic voltammograms of Fe52gC;
(B) cycling performance of Fe52@C and pristine Fe52. Red cross indicates result from reference 28 (0.58C).
[0047] Figure 35. Representative (A) XRD pattern, (B) TEM image, (C) STEM
image and (D) EDX spectrum for FeSn2@C nanocomposite.
cycling performance of FeSn2@C and pristine FeSn2 at 0.1C.
[0049] Figure 37. Representative (A) XRD patterns of the embedded carbon composites involving iron/iron oxides; (B) TEM image of 7 -Fe203@C composite;
(C) and (D) XRD pattern and TEM image of V205gC composite; (E) and (F) XRD pattern and TEM
image of Ti02@C composite.
[0050] Figure 38. Representative (A) Cyclic voltammograms of 7 -Fe203@C; (B) cycling performance of 7 -Fe203@C at 0.5C, 1C and 2C and pristine Fe203 at 0.5C.
[0051] Figure 39. Representative infrared spectra of crosslinked PAN-DVB, Fe(C10H19C00)3 and PAN-iron composite. Inset: close-up of 1600-1700 cm-1, normalized using peak at 2930 cm-1.
[0052] Figure 40. Representative oxidative TGA curves for FeS2@C, FeSn2@C and r -Fe203@C
[0053] Figure 41. Representative voltage-capacity profiles for FeS2@C
composite run at 0.2C and 1C.
[0054] Figure 42. Representative voltage-capacity profiles for FeSn2@C
composite run at 0.1C.
[0055] Figure 43. Representative voltage-capacity profiles for r -Fe203@C composite run at 0.5C, 1C and 2C.
DETAILED DESCRIPTION OF THE INVENTION
[0056] The present invention provides hybrid materials, nanocomposite materials, methods of making such materials. Also provided are uses of such materials.
[0057] The hybrid/in situ approach of the instant invention provides homogeneous dispersion of the metal precursor in the polymer matrix (e.g., a cross-linked polymer matrix) and thus the pyrolysis of the hybrid is able to yield composites with particles uniformly dispersed in the matrix. Additionally, the synthesis of the composite via simultaneous creation of the active material and the carbon matrix reduces the complexity of synthesis procedure and lends itself to the development of low-cost/scalable production processes.
[0058] In an aspect, the present invention provides a hybrid material.
The hybrid material is a polymer comprising a metal precursor. The metal precursor is chemically bonded to the polymer. During pyrolysis of the hybrid material, nanoparticles are formed metal precursor compounds embedded in a polymer.
[0059] By chemically bonded it is meant that the metal precursor (i.e., a chemical moiety of or metal center of the metal precursor) is chemically bonded via a chemical bond (e.g., covalent bond, coordinate covalent bond, or ionic bond) to the polymer.
[0060] A variety of polymers can be used. Suitable polymers can be thermally degraded (i.e., pyrolysed) to provide a graphitic material or partially graphitic material. The resulting material is electrically conducting. The polymer can be a homopolymer or a copolymer. Examples of suitable polymers include poly(acrylonitrile), polyvinylpyrroilidone, polypyrrole, polyacetylene, polythiophene, polyphenylene vinylene, polyphenylene sulfide, polysaccharides (e.g., galactose, maltose, and glucose), acrylonitrile-divinylbenzene copolymer, phenol resin, and resorcinol-formaldehyde copolymer.
[0061] The metal precursor is a compound with a metal center and one or more ligands. The metal precursor compounds are chemically bonded to the polymer.
The metal precursor is uniformly distributed throughout the polymer. The metal precursors form nanoparticles in situ during pyrolysis of the polymer. Depending on the components of the reaction mixture, it may be desirable the metal precursor be water soluble.
The metal precursors are present in the hybrid material at from 10 % by weight to 90% by weight, including all integer % by weight values and ranges therebetween. Examples of suitable metal precursor compounds include metal carboxylates, metal coordination compounds (e.g., metal thiolates), amino acid metal salts, and other metal-organic compounds.
[0062] By uniformly distributed it is meant there is a homogeneous distribution of a preponderance of the metal precursors in the polymer-based hybrid materials, or a homogeneous distribution of a preponderance of the nanoparticles in the nanocomposite materials. For the hybrid materials, there is a substantial absence of phase separation (e.g., no observed phase separation) between the polymer and metal precursors and/or a substantial absence of metal precursor aggregates (e.g., no metal precursor aggregates are observed). For the nanocomposite materials, there is a substantial absence of phase separation between the carbon matrix and nanoparticles (e.g., no observed phase separation) and/or a substantial absence of particle-particle aggregates (e.g., no particle-particle aggregates are observed).
[0063] The metal precursor can be a metal carboxylate. In an embodiment, the metal carboxylate comprises an alkyl moiety. The alkyl moiety can be a C6 to C30 alkyl moiety, including all integer number of carbons and ranges therebetween. The moiety can be substituted with a reactive chemical moiety (e.g., a carbon-carbon double bond, and amine, hydroxyl, carboxylate groups and combinations of such groups (which can hydrogen bond with moieties in the polymer/monomer)) that can be incorporated in the polymer by a polymerization reaction. Examples of suitable metal carboxylates include alkyl metal carboxylates (e.g., iron undecylenate, manganese undecylenate, tin undecylenate, or vanadium undecylenate), metal citrates (e.g., iron citrate, manganese citrate, tin citrate, and vanadium citrate), amino acid metal salts (e.g., iron aspartate), and other metal-organic compounds (e.g., iron gluconate).
[0064] In an embodiment, the metal precursor has a chemical moiety that reacts with the polymer or monomer to form a covalent bond. For example, the metal precursor is a metal carboxylate (e.g., iron undecylenate, manganese undecylenate, tin undecylenate, or vanadium undecylenate) having a carbon-carbon double bond that is copolymerized with a monomer or monomers.
[0065] The metal precursor can be a metal coordination compound. In an embodiment, the metal center (e.g., Mo) of the metal precursor (e.g., ammonium molybdenum tertrathiolate) is chemically bound to the polymer via a coordinate covalent bond.
[0066] In an aspect, the present invention provides a nanocomposite material. The nanocomposite material has nanoparticles embedded (e.g., encapsulated) in a continuous phase of carbon (i.e., a carbon matrix). In an embodiment, the nanocomposite material comprises a plurality of nanoparticles embedded in a carbon matrix.
[0067] The nanocomposite materials can include a variety of nanoparticles. For example, the nanoparticles can be metal nanoparticles, metal oxide nanoparticles, metal halide (e.g., metal fluoride) nanoparticles, metal boride nanoparticles, metal phosphate nanoparticles, or combinations of such nanoparticles. The nanoparticles can include a variety of metals. The nanoparticles can have multiple metals (e.g., metal alloys and mixed metal oxides). In the case of multiple metals in the nanoparticles, depending on the composition the individual nanoparticles can have mixed composition (alloyed nanoparticles) or a mixture of nanoparticles with different composition. For example, Feo 75Mno 250 can provide alloyed nanoparticles and Sn/FeSn2 can provide a mixture of nanoparticles with different compositions. The nanoparticles can be crystalline or amorphous.
[0068] Examples of suitable metal nanoparticles include Fe, Mn, and FeSn2, FeNi3, Al, Sn, Ge, and Si. Examples of suitable metal oxides include Fe203 (e.g., 7-Fe203), Fe304, Mn203, M-Mn204 (M = Li, Na, K), M003, V205, T102, M4T15012 (M = Li, Na, K, Ag), Sn02, SnO, Co304, and MCo02 (M = Li, Na, K). Examples of suitable metal sulfides include MoS2, MoS3 FeS2, FeS, Fei,S(x=0-0.2), CoS, CuS, Cu2S, TiS2, and M2S (M = Li, Na, K).
Examples of suitable metal borides include TiB2, VB2, and LiBio. Examples of a suitable metals fluoride are CuF2, FeF2, and FeF3. Examples of suitable metal phosphates include MFePat (M=Li, Na, K) and LiMnxFei,PO4.
[0069] The nanoparticles are present at 10 % by weight to 90 % by weight, including all integer % by weight values and ranges therebetween. In an example, the nanoparticles are present at 40 % by weight to 90 % by weight.
[0070] Based on the composition of the nanoparticles and the methods used to form the nanoparticles, the nanoparticles can have a variety of shapes and sizes.
In various examples, the nanoparticles have a spherical shape (e.g., Fe203 nanoparticles) or a rectangular shape (e.g., MoS2 nanoparticles). In the case of spherical nanoparticles, the diameter of the nanoparticles is from 5 nm to 500 nm, including all integer nanometer values and ranges therebetween, in size. In the case of rectangular nanoparticles, the nanoparticles have a length of 20 to 100 nm, including all integer nanometer values and ranges therebetween, and a thickness of 5 to 20 nm, including all integer nanometer values and ranges therebetween. The size can be an average size. For example, the size of individual nanoparticles and the average nanoparticle size can be measured by transmission electron microscopy.
[0071] The nanoparticles have a narrow size distribution. For example, the nanoparticles have a polydispersity index of 1.001 to 1.05, including all values to 0.001 and ranges therebetween. In an embodiment, the nanoparticles are monodisperse (i.e., the fraction of nanoparticles within one standard deviation from the number average size is greater than or equal to 75%). In another embodiment, the fraction of nanoparticles within one standard deviation from the number average size is greater than or equal to 90%.
[0072] The nanoparticles are embedded in a carbon matrix. The carbon matrix is a partially graphitic or graphitic material. The graphitic material is a material consisting of graphite. The partially graphitic material is a material comprising graphite that may also contain disordered graphitic lattices and/or amorphous carbon. The presence of graphite, disordered graphitic lattices and/or amorphous carbon can be determined by techniques such as, for example, XRD and Raman spectroscopy. The carbon matrix is porous and amorphous.
Aggregation of the nanoparticles in the carbon matrix is not observed (e.g., by TEM, SEM, or as described herein.
[0073] The carbon matrix can have a range of porosity based the materials and conditions used to form the matrix. In various examples, the pores of the carbon matrix are less than 100nm, less than 20nm, or less than 5nm.
[0074] The nanocomposite materials exhibit desirable properties. The nanocomposite material is conductive. The material can have a conductivity of 10-5 to 100 S/cm. The material can have a Vickers Hardness of the composite is 1 to 40 GPa. The material can have a fracture toughness of the composite is 5 to 25 MPa 111112. In various examples, the capacity retentions of the composites in lithium-ion batteries is greater than 90%, greater than 95%, greater than 98% in 100 cycles at a 1C charge/discharge rate.
[0075] In an aspect, the present invention provides methods of forming a material.
The material can be a hybrid material or nanocomposite material as described herein. In an embodiment, the hybrid material is made by a method described herein. In an embodiment, the nanocomposite material is made by a method described herein.
[0076] In an embodiment, the method for forming a material comprises the steps of:
contacting one or more monomers, one or more metal precursor compounds, optionally, an initiator, and, optionally, one or more solvents to form a reaction mixture, heating the reaction mixture such that a hybrid material comprising a plurality of metal precursor compounds chemically bonded to the polymer matrix is formed and, optionally, isolating the hybrid material.
[0077] In an embodiment, the reaction mixture comprises: a first (e.g., bulk) monomer (e.g., acrylonitrile), optionally, a second (vinyl or cross-linking) monomer (e.g., divinyl benzene), a metal precursor compound (metal carboxylate) (e.g., iron undecylenate), an initiator (e.g., AIBN), a (anionic) surfactant (e.g., sodium dodecyl sulfate), water, and one or more organic solvents such that a reaction mixture that is an aqueous emulsion is formed.
In this embodiment, the reaction mixture is, optionally, subjected to high-shear mixing such that a miniemulsion having oil-in-water droplets with an average size of 0.01 microns to 0.5 microns if formed. For example, high shear mixing (for bench-top scale synthesis) can be provided by a sonication horn operated at 500W and at 20kHz with 50%
amplitude. A larger scale reaction may require higher power to achieve the desired shear.
[0078] In another embodiment, the reaction mixture comprises: a first (e.g., bulk) monomer (e.g., resorcinol), and, optionally, a second (bulk) monomer (e.g., formaldehyde), a metal precursor compound (e.g., ammonium tetrathiomolybdate), and water.
or four) of metal precursors, where the metal precursors each comprise a different metal.
[0080] The hybrid material can be pyrolysed to form a nanocomposite material.
Nanoparticles are formed in situ from the metal precursor compounds as a result of the pyrolysis process. The pyrolysis process can be carried out in a single step or can have multiple steps. For example, carbonization can comprise consecutive, stabilization, carbonization, and graphitization steps. The determination of pyrolysis conditions is material dependent and is within the purview of one having skill in the art. For example, a single step pyrolysis step can be from 500 to 900 C, including all values to the degree Celsius and ranges therebetween. For example, a multiple step pyrolysis can be 320 C for lhour for stabilization and 500 C for 2hrs for carbonization. Higher temperatures may be required for complete graphitization.
[0081] The pyrolysis step (or one of the steps of a multiple step pyrolysis) can be carried out in an atmosphere comprising a variety of gases. A mixture of gases can be used.
For example, the pyrolysis step can be carried out in air (or an oxygen containing atmosphere) or an inert atmosphere (e.g., a nitrogen atmosphere, an argon atmosphere, or a mixture thereof). For example, a reactive gas such as carbon dioxide (an oxidizing gas) can be used to provide increased mesopore and micropore content of the carbon matrix relative to pyrolysis in the absence of such gas.
[0082] In an embodiment, the method further comprises the step of pyrolysing the hybrid material, such that a nanocomposite material comprising a plurality of metal oxide nanoparticles (or metal nanoparticles) embedded in a carbon matrix is formed.
[0083] In an embodiment, the resorcinol-formaldehyde hybrid polymers are pyrolysed in an atmosphere comprising carbon dioxide or in a carbon dioxide gas atmosphere. The carbon dioxide is present at atmospheric pressure or substantially atmospheric pressure. The use of carbon dioxide in the pyrolysis step can provide a carbon matrix having a desirable morphology. For example, the carbon matrix can have an interconnected pore structure and higher surface area than materials obtained without using carbon dioxide in the pyrolysis step. For example, pyrolysis of a resorcinol-formaldehyde hybrid polymer at 800 C in a CO2(g) atmosphere provides carbon with broad pore size distribution (including mesopores and micropores) with graphene-like sheet textures. Using carbon dioxide in the pyrolysis step can result in a loss of mass in the resulting composite material and increases the interconnectivity of the pores of the carbon matrix.
The nanoparticles of the starting nanocomposite are subjected to reaction conditions that result in formation of a portion of or all nanoparticles having a different chemical composition than the starting nanoparticles. For example, metal oxide nanoparticles are reacted such that metal, metal halide, metal sulfide, and metal phosphate nanoparticles are formed or metal sulfide nanoparticles are reacted such that metal oxides, metal halide, metal, or metal phosphate nanoparticles are formed.
[0085] In an embodiment, the method further comprises reducing the metal oxide nanoparticles of the nanocomposite material comprising a plurality of metal oxide nanoparticles embedded in a carbon matrix by contacting the nanocomposite material with a reductant (e.g., hydrogen gas) or heating the nanocomposite material under inert conditions (to a temperature higher than the carbonization temperature (carbon serves as the reductant)), such that a nanocomposite material comprising a plurality of metal nanoparticles embedded in a carbon matrix is formed.
[0086] In an embodiment, the method further comprises contacting the nanocomposite material comprising a plurality of metal oxide nanoparticles embedded in a carbon matrix with a sulfur compound (e.g., sulfur), halide compound (e.g., fluoride compound), or phosphate compound, such that a nanocomposite material comprising a plurality of metal sulfide, metal halide, or metal phosphate nanoparticles embedded in a carbon matrix is formed.
[0087] In an embodiment, the method further comprises reducing the metal sulfide nanoparticles of the nanocomposite material comprising a plurality of metal sulfide nanoparticles embedded in a carbon matrix by contacting the nanocomposite material with a reductant (e.g., hydrogen gas) or heating the nanocomposite material under inert conditions (to a temperature higher than the carbonization temperature (carbon serves as the reductant)), such that a nanocomposite material comprising a plurality of metal nanoparticles embedded in a carbon matrix is formed.
[0088] In an embodiment, the method further comprises contacting the nanocomposite material comprising a plurality of metal sulfide nanoparticles embedded in a carbon matrix with an oxygen compound, halide compound, or phosphate compound, such that a nanocomposite material comprising a plurality of metal oxide, metal halide, or metal phosphate nanoparticles embedded in a carbon matrix is formed.
hybrid material. Examples of suitable bulk monomers include acrylonitrile, resorcinol, formaldehyde, vinylpyrrolidone, vinyl alcohol, acrylic acid, and phenol.
[0090] The cross-linking monomer forms cross links in the polymer.
Examples of suitable cross-linking monomers include divinylbenzene, 1,4-butadiene, isoprene, vinylsilane, and sulfur.
[0091] Any initiator that initiates the polymerization of the monomers can be used.
For example radical polymerization initiators can be used. Examples of suitable initiators include 2,2'-azobisbutyronitrile (AIBN), benzoyl peroxide, dicumyl peroxide, potassium persulfate, and 4,4' -azobis(4-cyanov aleric acid).
[0092] Any surfactant that forms a suitable aqueous emulsion can be used. For example anionic surfactants can be used. Examples of suitable surfactants include sodium dodecyl sulfate, hexadecyltrimethylammonium bromide, and polysorbates.
[0093] A single solvent or mixture of solvents can be used. For example, the solvent can be water. In the case where water is a solvent, depending on, for example, the components of the reaction mixture, it may be desirable to have the pH of the reaction mixture be greater than 7. Examples of suitable solvents include water, toluene, and cyclohexane.
[0094] The selection of reaction conditions that result in formation of the desired nanoparticle composition is within the purview of one having skill in the art.
The polymerization temperature for acrylonitrile is typically 60-80 C.
[0095] The steps of the method described in the various embodiments and examples disclosed herein are sufficient to produce hybrid materials and/or nanocomposite materials of the present invention. Thus, in an embodiment, the method consists essentially of a combination of the steps of the methods disclosed herein. In another embodiment, the method consists of such steps.
[0096] In an aspect, the present invention provides devices comprising the hybrid material or nanocomposite materials described herein. Examples of such devices include batteries (e.g., secondary batteries), on-chip inductors. Such device structures and methods of making such structures are known in the art.
[0097] In an embodiment, the present invention provides an electrode comprising a nanocomposite material. In an embodiment, a device comprises an electrode (e.g., an anode) comprising the nanocomposite material. In an embodiment, the present invention provides an on-chip inductor comprising the nanocomposite material. In an embodiment, a device nanocomposites containing iron or iron/nickel alloy nanoparticles.
[0098] The following examples are presented to illustrate the present invention. They are not intended to limiting in any manner.
[0099] This example describes the synthesis and characterization of examples of hybrid materials and nanocomposite materials of the present invention.
[0100] An in situ, scalable method for creating a variety of transition metal oxide¨
carbon nanocomposites was developed based on free-radical polymerization and cross-linking of poly(acrylonitrile) in the presence of the metal oxide precursor containing vinyl groups. The approach yields a cross-linked polymer network, which uniformly incorporates nanometer-sized transition metal oxide particles. Thermal treatment of the organic¨inorganic hybrid material produces nearly monodisperse metal oxide nanoparticles uniformly embedded in a porous carbon matrix. Cyclic voltammetry and galvanostatic cycling electrochemical measurements in a lithium half-cell are used to evaluate the electrochemical properties of a Fe304¨carbon composite created using this approach. These measurements reveal that when used as the anode in a lithium battery, the material exhibits stable cycling performance at both low and high current densities. The polymer/nanoparticle copolymerization approach can be readily adapted to synthesize metal oxide/carbon nanocomposites based on different particle chemistries for applications in both the anode and cathode of LIBs.
[0101] A facile, scalable emulsion polymerization technique for synthesizing transition metal oxide nanoparticles embedded in a porous carbon matrix has been reported.
The method (illustrated in Figure 1) relies upon co-polymerization and cross-linking of the carbon precursor (acrylonitrile) and the nanoparticle precursor in a single-step; it yields polymer¨nanoparticle hybrids with uniform particle distributions at high nanoparticle loadings. The procedure is also applicable for large-scale production of metal oxide¨carbon composites required for commercial-scale LIB manufacturing processes. The procedure was demonstrated by using a high-capacity (924 mA h g-1) transition metal oxide (Fe304) and show that it is adaptable to other oxides.
[0102] A nanocomposite of metal oxide/metal and carbon has been synthesized via a polymerization-carbonization process. A metal precursor (a carboxylic acid salt of the metal), soluble in nonpolar solvents, is mixed with a monomer, a cross-linking agent and a surfactant yield a composite of polymer nanoparticles encapsulating the iron precursor.
The material is then separated from the liquid phase and carbonized to give a composite material of metal oxide/metal-carbon nanoparticles, which may be used as the active electrode material for -- lithium-ion batteries. Fe304 was demonstrated as an example compound but the method is applicable to various metal oxides/metals. The method can also be extended to synthesize nanocomposites consisting of nanoparticles of other materials (e.g., other compounds which contain the metal such as CoS or a metal fluoride such as CuF2) embedded in a carbon matrix, through ex situ treatment of metal/carbon composites with sulfur, fluorine, and other -- materials (see, e.g., Example 2).
[0103] Reagents used in the study were purchased from Sigma-Aldrich unless otherwise specified and used without purification. Iron undecylenate was synthesized by the following procedure. 10.8 g (40 mmol) of FeC13=6H20, 4.8 g (0.12 mol) of NaOH
and 22.1 g (0.12 mol) of undecylenic acid were added to a mixture of 80 ml of ethanol, 60 ml of water -- and 140 ml of hexane under vigorous stifling. The mixture was heated at 70 C for 3 hours and then the organic phase was collected using a separation funnel. After washing with water for 3 times, hexane was driven off from the mixture using a rotary evaporator to obtain iron undecylenate, a waxy solid.
[0104] In a typical reaction, 2 ml acrylonitrile (AN), 2 ml divinylbenzene (DVB) and -- 1.8 g of iron undecylenate were mixed to form a homogeneous solution. 3 mg of azobisisobutyronitrile (AIBN) and 100 mg sodium dodecyl sulfate (SDS) were added to 25 ml of water and the former solution introduced into the aqueous phase under sonication with a Sonics VCX500 horn (500 W, 20 kHz, amplitude 50%). The mixture was sonicated for 3 minutes and after a stable emulsion was formed, heated at 70 C for 12 h.
Sodium chloride -- was added to induce aggregation of the resultant polymer¨inorganic hybrid particles, which were collected by centrifugation. The material obtained was heated in a nitrogen atmosphere, first to 320 C, held at this temperature for 1 h, then to 500 C and held for 2 h to obtain the final metal-oxide/carbon nanocomposite product.
[0105] The crystal structures of the particles were characterized using a Scintag Theta¨theta PAD-X X-ray Diffractometer (Cu Ka, ) = 1.5406 A) and their morphologies were studied using an FEI Tecnai G2 T12 Spirit Transmission Electron Microscope (120 kV).
Raman spectra were taken using a Renishaw In Via Confocal Raman Microscope.
Thermogravimetric analysis was performed using a TA Instruments Q5000 IR
Thermogravimetric Analyzer. Electrical conductivity measurement was made using a Lucas cm'. Gas adsorption analysis for porous materials was performed using a Micromeritics ASAP 2020 Accelerated Surface Area and Porosimetry System.
[0106] Electrochemical characterization of the composites as anode materials in rechargeable lithium-ion batteries was performed at room temperature in homemade Swagelok-type cells. The working electrode consists of 80 wt% of the active material, 10 wt% of carbon black (Super-P Li from TIMCAL) as a conductivity aid, and 10 wt%
of polymer binder (PVDF, polyvinylidene fluoride, Aldrich). Lithium foil was used as the counter and reference electrodes. A 1 M solution of LiPF6 in a 50 : 50, w/w mixture of ethylene carbonate and diethyl carbonate was used as the electrolyte. Celgard polypropylene membranes are used as the separator. Assembly of cell was performed in a glove box with moisture and oxygen concentrations below 1 ppm. The room-temperature electrode capacities were measured using Neware CT-3008 battery testers.
[0107] Powder X-ray diffraction was performed to determine the crystalline phase of the transition metal oxide. The XRD results, shown in Figure 2(a), match well with those of magnetite (JCPDS card no. 19-629). The broad signal in the range of 20-30 may be due to the presence of non-crystalline carbon in the composite, because the most intense reflection for graphitic carbon (002 layer) should appear at 26.8 . From the ScheiTer's formula, the average crystallite size of the Fe304 phase is found to be 21 nm.
[0108] Transmission Electron Micrographs (TEM) for the polymer¨particle complex are shown in Figure 3(a). The material generally consists of particles with sizes in the range 200-400 nm aggregated together. Energy Dispersive X-Ray Spectroscopy (EDX) was performed on the complex, as shown in Figure 3(c), which confirms that iron has been successfully incorporated in the complex. The morphology of the material after calcination is shown in Figure 3(b). It consists of uniformly sized Fe304 nanoparticles embedded in a carbon matrix and the size is consistent with the average crystallite size calculated from the X-Ray diffractograms (21 nm). Oxidative thermal gravimetric analysis (TGA) may be used to measure the weight fraction of active material Fe304 in the composite and the data are shown in Figure 3(d). The material is heated to 700 C under air so that Fe304 is oxidized to Fe203 and carbon is oxidized to CO2. From the remaining weight (of Fe203), the original weight fraction of Fe304 is calculated to be 66%.
[0109] Other carboxylic acid salts of iron have been used as the precursor, for example iron oleate, but the amount of Fe304 eventually encapsulated in the product can be substantially lower (e.g., 33%) than for iron undecylenate. The higher molecular weight of efficient incorporation in the polymer complex. In addition, the fractional weight loss of conversion of Fe(ole)3 to Fe304 (91%) is larger than conversion of Fe(ole)3 to Fe304 (87%), because of the larger molecular weight of Fe(ole)3. Iron(III) acetylacetonate (Fe(acac)3), which has a lower molecular weight than Fe(undec)3 was also investigated. In this case, the higher water solubility of the particle precursor does not allow formation of stable micelles required for emulsion polymerization.
[0110] Polyacrylonitrile is frequently used to synthesize graphitic materials through calcination at high temperatures. To obtain highly graphitic carbon, PAN
should be subjected to three consecutive processes, namely, stabilization, carbonization and graphitization. In the stabilization step, PAN is heated to 200-300 C in air and converted to a cyclic or a ladder compound, followed by treatment in nitrogen atmosphere to about 1000 C to achieve carbonization of the material. The third step, known as graphitization, is to heat the material to 1500-3000 C under argon atmosphere to improve the ordering and orientation of the crystallites. Because the present system contains metal oxides, if the material is heated to temperatures above ¨ 700 C for the sake of increasing the graphite content in the product, there is the possibility of carbon reducing the metal oxide to pure metal. As a compromise, a carbonization protocol requiring heating the material at 500 C in dry N2 was used.
[0111] The Raman spectrum of the Fe304¨C composite is shown in Figure 4. It is immediately noticeable that the spectrum contains two prominent peaks at around 1350 and 1590 wavenumbers. Raman spectra for carbon materials usually contain several peaks. In particular, the spectrum can be deconvoluted to five bands, conesponding to ideal graphite (G 1580 cm-1), a disordered graphitic lattice (D1 1350 cm-1, D2 1620 cm-1 and cm 1), or amorphous carbon (D3 1500 cm 1). G and D2 both come from sp2 carbon vibrations, which can be difficult to distinguish, and in some works have been treated as one single component in the fitting procedure. Lorentzian functions were used in the fitting and the calculated positions for the peaks are: G 1596 cm-1, D1 1349 cm-1, D3 1471 cm-1, and D4 1230 cm-1. This analysis indicates the carbon obtained in the composite is partially graphitic.
[0112] Magnetite has the formula Fe2 [Fe3+2104 and adopts an inverse spinet structure. In each unit cell (containing 8 multiples of Fe304), 8 out of 16 Fe3+ ions occupy 8 out of the 64 tetrahedral sites and all the Fe2+ ions and the remaining 8 Fe3+
ions are distributed in 16 out of 32 octahedral sites. Lithiation of Fe304 follows the following pathway:
" -(Piev JO., (Maw 13 IrePizaw 2) _________________________________ 3t41...0 =4=3re (Maw 3) [0113] Here parentheses denote ions in tetrahedral sites and square brackets denote ions in octahedral sites. During the insertion of up to 1.0 Li, the Li + ions fill up octahedral vacancies, with Fe3+ in the tetrahedral sites displaced to octahedral sites, leading to the formation of a rock-salt-like structure of Li1.0Fe304 at the end of this step.
Further insertion of lithium involves the filling of the tetrahedral sites by Li + ions. Metallic iron is extruded from the rock-salt structure to accommodate the incoming Li + ions.
[0114] Cyclic voltammograms for Fe304¨C composites are shown in Figure 5(a) (scan rate = 0.2 mV s-1). The patterns are consistent with the CV results from other reports on Fe304¨C composites. In the anodic process, starting from the second cycle, the lithium intercalation occurs mainly at around 0.7 V and in the cathodic process the oxidation of Fe occurs at around 1.8 V. In the first cycle, the intercalation occurred at a lower voltage of around 0.4 V, probably because of an overpotential arising from the crystal structure changes from the inverse spinet structure to the rock salt type structure. The voltage¨capacity profiles for the complex cycled at different charging rates (1 C or 0.5 C) are shown in Figure 5(b).
The lithium intercalation plateaus are not as flat for the Fe304 in carbon composites compared to the pure oxide, probably because of reduction in crystallinity and/or change in surface site energetics during the process of the carbon formation for the composite.
[0115] Cycling performance data for the Fe304¨C composites are shown in Figure 6.
The material was cycled at 1 C and 0.2 C, respectively for 100 cycles and the performance under different charging rates ranging from 0.5 C to 5 C was also studied.
The capacities are calculated based on the metal oxide mass because the capacity¨voltage profiles do not indicate significant contribution from lithium intercalation into the carbon host. It is apparent from Figure 6 that the composites show very stable performance and little fading for 100 cycles, even at 1 C charging rate. The performance is also stable for higher charging rates (20 cycles are shown as examples). The performance of bare Fe304 nanoparticles (50 nm in size, commercially available from Alfa Aesar) as the anode material is also shown in Figure 6(d) for comparison purposes; the clear improvements provided by the composite materials are visible from this plot. The performance of pure carbon made from pyrolysis of PAN¨DVB at to the lithium storage capacity.
[0116] The stable electrochemical performance of the Fe304-C
nanocomposites can be attributed to different features of the materials. Considering the relatively low electronic conductivity of the carbon component, it is not a consequence of enhanced electronic transport afforded by the carbon. The uniformly sized Fe304 nanoparticles are embedded in the carbon matrix, which might serve to alleviate the volume change incurred during the repeated cycling. A porous, mechanically flexible reinforcement that allows good penetration by the electrolyte into the active material is therefore considered advantageous. Nitrogen adsorption analysis was performed on the composite and the surface area measured by the BET method is 122 m2 g-1, with the isotherms and the pore size distribution for the composite (calculated using BJH method) shown in Figure 7. The BET surface area of pure carbon obtained from pyrolysis of the PAN-DVB polymer (without Fe304 nanoparticles) is about three times higher, 369 m2 g-1. The pore size distribution results show that most of the pores are less than 10 nm in size.
[0117] The size of the Fe304 nanoparticles also seems to be an important factor in determining the electrochemical performance. Average diameters of Fe304 particles synthesized using hydrothermal/solvothermal methods are usually greater than 150 nm because the particles are typically aggregates of smaller primary crystallites. In the current method, the size of the Fe304 nanoparticles is relatively small and the greater surface area and shorter diffusion length may allow easier access of the active material by the lithium ions.
[0118] The method developed for creating Fe304-C composites can be applied to synthesize nanocomposites of various other metal oxides (or other related materials such as pure metal) embedded in carbon matrices. Another interesting material is MnO, which has a theoretical lithium storage capacity of 755 mA h g-1. MnO undergoes conversion reaction in lithium-ion batteries: 2Li + MnO ¨> Mn + Li20 and upon lithium insertion, Mn grains <5 nm in size are formed. MnO-C composites can be synthesized using manganese(II) undecylenate as the precursor. Figure 8(a) shows the X-ray diffractogram for the MnO-C
composite, which matches well with MnO (JCPDS card no. 07-230). Again a broad band is observed in the range of 20-30 , but no sharp peak could be found at 26.8 , indicating that the carbon component is largely amorphous. TGA is used to determine the fraction of MnO
in the composite. Upon heating to 700 C in air, MnO is oxidized to Mn203 and the weight fraction of MnO in the composite is calculated to be 58% assuming all the remaining material is case of Fe304, MnO nanoparticles embedded in a carbon matrix are obtained.
[0119] A typical cyclic voltammogram for the MnO¨C composite is shown in Figure 9(a) and lithium insertion/Mn2+ reduction seems to occur at around 0.5 V
against Li/Lit, which is consistent with previous reports on MnO anode materials.
Voltage¨capacity curves at 0.5 C and 1 C charging rates are shown in Figure 9(b) and cycling data for the composite run at 1 C and 0.2 C, and at varied charging rates are shown in Figure 9(c).
Similar to what was observed for the Fe304¨C composite, little capacity fade is observed even when the material is subject to 1 C charging rate for over >100 cycles. Cycling at higher charging rates is also seen to give stable performance. Therefore a prominent feature of the current protocol is the ability to yield materials with stable performance at moderately high charging rates.
[0120] In conclusion, a one-step free-radical polymerization method is used to synthesize cross-linked metal-oxide/poly(acrylonitrile) nanocomposites.
Pyrolysis of the composite at moderate temperatures in an inert atmosphere yields metal-oxide/carbon particles comprised of uniformly distributed metal oxide nanoparticles in a partially graphitic, but poorly conducting carbon host. The versatility of the approach has been demonstrated using two different metal oxides, Fe304 and MnO. When evaluated as anode materials in lithium-ion batteries, composites of both materials display stable performance at low and high cun-ent densities.
[0121] This example describes the synthesis and characterization of examples of hybrid materials and nanocomposite materials of the present invention.
[0122] Synthesis of LiFePO4@C nanocomposite. 108mg Li0H, 221mg H3PO4 and 660mg L-ascorbic acid are dissolved in 10m1 DI water, to which 116mg Fe304@C
nanocomposite powder is added. The solution is loaded into a pressurized container and heated at 270 C for 12hr. The powder obtained is centrifuged and washed with water.
[0123] Synthesis of Mn075Fe0250@C nanocomposite. Manganese (II) undecylenate is synthesized using the same method as iron (III) undecylenate, with MnC12 as the Mn precursor. 1.58g manganese (II) undecylenate and 0.75g iron (III) undecylenate are mixed to form a homogeneous mixture, and polymerization with acrylonitrile and divinylbenzene is performed using the same method as used for iron (III) undecylenate alone. The polymerization product is collected ant heat treated in the same way to obtain Mno 75Fe0 250@ C nanocomposite.
H3PO4 and 49mg H3P03 are dissolved in 10m1 DI water, to which 142mg Mn075Fe0250@C
nanocomposite powder is added. The solution is loaded into a pressurized container and heated at 270 C for 12hr. The powder obtained is centrifuged and washed with water.
[0125] The synthesis, structural characterization and electrochemical performance of MoS2¨carbon nanostructures is described in this example.
[0126] Composites of MoS2 and amorphous carbon were grown and self-assembled into hierarchical nanostructures via a hydrothermal method. Application of the composites as high-energy electrodes for rechargeable lithium-ion batteries was investigated. The critical roles of nanostructuring of MoS2 and carbon composition on lithium-ion battery performance are described. Pure MoS2 and 22 wt% carbon containing MoS2 materials are designated as MS-0 and MS-22 respectively.
[0127] Morphological investigations using SEM (Figure 18a) reveal that the product obtained via the hydrothermal treatment of the molybdenum sol in presence of carbon precursors (resorcinol and formaldehyde) takes the form of open structure of MoS2 and carbon. The TEM images of MS-22 (22 wt% carbon), as shown in Figures 18b and c, indicate that MoS2 in the composites are in the form of stacked nanosheets homogeneously embedded in a very thin matrix of amorphous carbon. The length and thickness of MoS2 nanosheets are about 40 and 10 nm respectively (inset of Figure 18b). It can be observed that the MoS2 sheets are composed of few MoS2 layers (-6 to 10 layers). A schematic of the in situ synthesis of MoS2¨carbon composites is shown in Figure 19A. In absence of resorcinol and formaldehyde, the MoS2 particles aggregate to form large MoS2 lumps (Figure 19B) as verified by the SEM and TEM images (Figures 18d and f). On the other hand, polycondensation of resorcinol with formaldehyde takes place during the hydrothermal process forming low density carbon gels. The MoS2 particles in the form of layers simultaneously crystallize during the hydrothermal process and are eventually uniformly dispersed in the carbon gel. The successive restacking of MoS2 layers is significantly inhibited by the carbon gel resulting in few layers of MoS2 nanosheet and consequently self-assembled in interconnected flakes resulting in three dimensional MoS2¨carbon nanostructures.
[0128] The X-ray diffraction patterns (XRD) of the MS-0 and MS-22 shows broad diffraction peaks which can be indexed to 2H polytype of MoS2 crystal structure with space composites, no peak shifts are observed suggesting that the MoS2 crystallites are unconstrained by chemical bonding to the carbon framework. Furthermore, no characteristic peak from graphitic carbon was detected in the XRD, indicating the formation of amorphous carbon. It can be observed that the intensity of (002) peak for MS-22 is relatively lower compared to pure MoS2 particles (see ESI, Figure 23). The peak at (002) is typically observed in bulk analogue. It suggests that the carbon inhibits the growth of (002) planes of MoS2 crystallites, which confines its growth in the plane favoring formation of few-layer nanosheets in the amorphous carbon matrix. The carbon content is estimated using thermogravimetric analysis; the results are depicted in (see ESI, Figure 24).
It is seen that there is successful incorporation of 11, 22, 32 and 41 wt% of carbon in MoS2-carbon nanostructures. The BET surface areas of MS-0, MS-22 and MS-41 are 3, 35 and 157 m2 g-1 respectively (see ESI, Figure 25). The increase in surface area with increasing carbon content is attributed to the porous nature of amorphous carbon.
[0129] The electrochemical properties and lithium battery performance of all MoS2-carbon composites using galvanostatic discharge and cyclic voltammetry measurements was investigated. Electrodes were prepared from the MoS2-carbon composites and a PVDf binder, i. e. , no carbon black or other conductivity aid was added. Figure 20 shows the galvanostatic charge (Li removal)/discharge (Li insertion) profiles obtained from pure and carbon-composited MoS2 at room temperature (25 C) and at a constant current density of 100 mA g-1 in the voltage range of 0.05-3 V. In the present study, pure MoS2 particle exhibited a discharge capacity of 2362 mA h g-1 in the Et discharge cycle (Figure 20a). Two potential plateaus at 1.1 V and 0.61 V corresponding to the formation of LixMoS2 and conversion of MoS2 to Mo respectively are also readily apparent from Figure 20. The pure MoS2 shows very poor Et charge and 2nd discharge capacities of 247 and 53 mA h g-1, respectively without any noticeable potential plateaus.
[0130] The MoS2-carbon nanocomposite structures all exhibit significantly improved capacity retention (Figures 20b and e). All MoS2-carbon composites manifest the prominent characteristic discharge potential plateaus at 1.1 V and 0.6 V in the Et discharge cycle and charge potential plateau at 2.3 V in all charge cycles (Figure 20b). During subsequent discharge cycles, the potential plateau observed at 0.6 V disappeared with emergence of two new inconspicuous potential plateaus at -1.9 V and 1.2 V (Figure 20b) which is in agreement with previous observations. The first discharge capacities of MS-11, MS-22, MS-32 and MS-41 are 2108, 1462, 1130, and 1078 mA h g-1 with coulombic efficiencies of 79%, 62%, 63%,
nanoparticles of the following phases: Fe, Fe304, Fe203, MnO, Mn304, Sn, Co, Co304, Cu, Cu0; an example of a TEM image of Cu@C composite.
[0023] Figure 11. Representative XRD patterns of nanocomposites embedding the nanoparticles of the following phases: Ti02(anatase), V205, ZnO, Zr02; an example of a TEM image of Ti02@C composite.
[0024] Figure 12. Scheme for synthesizing Co@C and CoS@C
nanocomposites;
representative XRD patterns of Co@C and CoS@C nanocomposites.
[0025] Figure 13. Representative XRD pattern for Fe304@C and LiFePO4@C
nanocomposites.
[0026] Figure 14. Representative TEM image for LiFePO4@C
nanocomposites.
[0027] Figure 15. Representative XRD pattern for Mn075Fe0250@C and LiMno 75Feo 25PO4@ C nanocomposites.
[0028] Figure 16. Representative TEM image for Mn075Fe0250@C
nanocomposite.
[0029] Figure 17. Representative TEM image for LiMn075Fe025PO4@C
nanocomposite.
[0030] Figure 18. Representative scanning electron micrographs of (a) MS-22, (d) MS-0; transmission electron micrographs of (b and c) MS-22, (e and MS-0;
insets of (b) shows Mo52 nanosheet; SAED patterns of MS-22 and MS-0 in the insets of (c) and (0 respectively.
[0031] Figure 19. An example of a schematic of the synthesis of (A) Mo52¨carbon nanostructure and (B) pure Mo52.
[0032] Figure 20. Representative galvanostatic charge¨discharge curves of (a) MS-0 and (b) MS-22 at a current density of 100 mA g-1; cyclic voltammetry (CV) curves of (c) MS-0 and (d) MS-22 at a scan rate of 0.2 mV 5-1; (e) cycling stability of pure Mo52 and various Mo52¨carbon composites; (f) variation of discharge capacity as a function of carbon weight fraction.
[0033] Figure 21. Representative Ex situ X-ray diffraction patterns of (a) Mo52¨
carbon (22 wt%) composite and (b) pure Mo52 after 1st discharge cycle. Peaks marked by *
corresponds to Cu current collector; scanning electron micrographs of 1st cycle discharged product of (c) MS-22 and (d) MS-0.
50% carbon black in the electrode composition at various current rates in the range of 0.4-4 A g-1.
[0035] Figure 23. Representative X-ray diffraction patterns of pure MoS2 and MoS2-carbon (22 wt %) composite.
[0036] Figure 24. Representative thermogravimetry analysis of pure MoS2, MS-11, MS-22, MS32 and MS-41.
[0037] Figure 25. Representative (a) N2 adsorption/desorption isotherms and (b) pore size distribution of pure MoS2, MS-22 and MS-41.
[0038] Figure 26. Representative transmission electron micrographs of (a) MS-11 and (b) MS-32.
[0039] Figure 27. (a) Representative cycling stability of pure MS-22 with 0%, 10%, 25% and 50% carbon black in the electrode at a current rate of (a) 100 mAg-1;
(b) at various current rates in the range of 0.4-4 Ag-1.
[0040] Figure 28. Representative cycling stability of 550 C and 700 C
calcined Mo52-carbon (22 wt %) composite at a current rate of (a) 100 mAg-1; (b) at various current rates in the range of 0.4-4 Ag-1.
[0041] Figure 29. Representative SAED patterns of (a) pure Mo52 and (b) Mo52-carbon (22 wt %) composite.
[0042] Figure 30. An example of a schematic of synthesis process for creating organic-inorganic copolymer hybrids.
[0043] Figure 31. Representative TEM images of Fe304@C nanocomposite (A) before cycling and (B) after 100 charge-discharge cycles.
[0044] Figure 32. An example of an overview of the platform for synthesizing nanocomposites with embedded structures involving different classes of materials.
[0045] Figure 33. Representative powder XRD patterns (A), TEM images for Fe@C
(B) and Fe52@C (C) composites and size distribution histograms for Fe@C (D) and Fe52@C
(E).
[0046] Figure 34. Representative (A) Cyclic voltammograms of Fe52gC;
(B) cycling performance of Fe52@C and pristine Fe52. Red cross indicates result from reference 28 (0.58C).
[0047] Figure 35. Representative (A) XRD pattern, (B) TEM image, (C) STEM
image and (D) EDX spectrum for FeSn2@C nanocomposite.
cycling performance of FeSn2@C and pristine FeSn2 at 0.1C.
[0049] Figure 37. Representative (A) XRD patterns of the embedded carbon composites involving iron/iron oxides; (B) TEM image of 7 -Fe203@C composite;
(C) and (D) XRD pattern and TEM image of V205gC composite; (E) and (F) XRD pattern and TEM
image of Ti02@C composite.
[0050] Figure 38. Representative (A) Cyclic voltammograms of 7 -Fe203@C; (B) cycling performance of 7 -Fe203@C at 0.5C, 1C and 2C and pristine Fe203 at 0.5C.
[0051] Figure 39. Representative infrared spectra of crosslinked PAN-DVB, Fe(C10H19C00)3 and PAN-iron composite. Inset: close-up of 1600-1700 cm-1, normalized using peak at 2930 cm-1.
[0052] Figure 40. Representative oxidative TGA curves for FeS2@C, FeSn2@C and r -Fe203@C
[0053] Figure 41. Representative voltage-capacity profiles for FeS2@C
composite run at 0.2C and 1C.
[0054] Figure 42. Representative voltage-capacity profiles for FeSn2@C
composite run at 0.1C.
[0055] Figure 43. Representative voltage-capacity profiles for r -Fe203@C composite run at 0.5C, 1C and 2C.
DETAILED DESCRIPTION OF THE INVENTION
[0056] The present invention provides hybrid materials, nanocomposite materials, methods of making such materials. Also provided are uses of such materials.
[0057] The hybrid/in situ approach of the instant invention provides homogeneous dispersion of the metal precursor in the polymer matrix (e.g., a cross-linked polymer matrix) and thus the pyrolysis of the hybrid is able to yield composites with particles uniformly dispersed in the matrix. Additionally, the synthesis of the composite via simultaneous creation of the active material and the carbon matrix reduces the complexity of synthesis procedure and lends itself to the development of low-cost/scalable production processes.
[0058] In an aspect, the present invention provides a hybrid material.
The hybrid material is a polymer comprising a metal precursor. The metal precursor is chemically bonded to the polymer. During pyrolysis of the hybrid material, nanoparticles are formed metal precursor compounds embedded in a polymer.
[0059] By chemically bonded it is meant that the metal precursor (i.e., a chemical moiety of or metal center of the metal precursor) is chemically bonded via a chemical bond (e.g., covalent bond, coordinate covalent bond, or ionic bond) to the polymer.
[0060] A variety of polymers can be used. Suitable polymers can be thermally degraded (i.e., pyrolysed) to provide a graphitic material or partially graphitic material. The resulting material is electrically conducting. The polymer can be a homopolymer or a copolymer. Examples of suitable polymers include poly(acrylonitrile), polyvinylpyrroilidone, polypyrrole, polyacetylene, polythiophene, polyphenylene vinylene, polyphenylene sulfide, polysaccharides (e.g., galactose, maltose, and glucose), acrylonitrile-divinylbenzene copolymer, phenol resin, and resorcinol-formaldehyde copolymer.
[0061] The metal precursor is a compound with a metal center and one or more ligands. The metal precursor compounds are chemically bonded to the polymer.
The metal precursor is uniformly distributed throughout the polymer. The metal precursors form nanoparticles in situ during pyrolysis of the polymer. Depending on the components of the reaction mixture, it may be desirable the metal precursor be water soluble.
The metal precursors are present in the hybrid material at from 10 % by weight to 90% by weight, including all integer % by weight values and ranges therebetween. Examples of suitable metal precursor compounds include metal carboxylates, metal coordination compounds (e.g., metal thiolates), amino acid metal salts, and other metal-organic compounds.
[0062] By uniformly distributed it is meant there is a homogeneous distribution of a preponderance of the metal precursors in the polymer-based hybrid materials, or a homogeneous distribution of a preponderance of the nanoparticles in the nanocomposite materials. For the hybrid materials, there is a substantial absence of phase separation (e.g., no observed phase separation) between the polymer and metal precursors and/or a substantial absence of metal precursor aggregates (e.g., no metal precursor aggregates are observed). For the nanocomposite materials, there is a substantial absence of phase separation between the carbon matrix and nanoparticles (e.g., no observed phase separation) and/or a substantial absence of particle-particle aggregates (e.g., no particle-particle aggregates are observed).
[0063] The metal precursor can be a metal carboxylate. In an embodiment, the metal carboxylate comprises an alkyl moiety. The alkyl moiety can be a C6 to C30 alkyl moiety, including all integer number of carbons and ranges therebetween. The moiety can be substituted with a reactive chemical moiety (e.g., a carbon-carbon double bond, and amine, hydroxyl, carboxylate groups and combinations of such groups (which can hydrogen bond with moieties in the polymer/monomer)) that can be incorporated in the polymer by a polymerization reaction. Examples of suitable metal carboxylates include alkyl metal carboxylates (e.g., iron undecylenate, manganese undecylenate, tin undecylenate, or vanadium undecylenate), metal citrates (e.g., iron citrate, manganese citrate, tin citrate, and vanadium citrate), amino acid metal salts (e.g., iron aspartate), and other metal-organic compounds (e.g., iron gluconate).
[0064] In an embodiment, the metal precursor has a chemical moiety that reacts with the polymer or monomer to form a covalent bond. For example, the metal precursor is a metal carboxylate (e.g., iron undecylenate, manganese undecylenate, tin undecylenate, or vanadium undecylenate) having a carbon-carbon double bond that is copolymerized with a monomer or monomers.
[0065] The metal precursor can be a metal coordination compound. In an embodiment, the metal center (e.g., Mo) of the metal precursor (e.g., ammonium molybdenum tertrathiolate) is chemically bound to the polymer via a coordinate covalent bond.
[0066] In an aspect, the present invention provides a nanocomposite material. The nanocomposite material has nanoparticles embedded (e.g., encapsulated) in a continuous phase of carbon (i.e., a carbon matrix). In an embodiment, the nanocomposite material comprises a plurality of nanoparticles embedded in a carbon matrix.
[0067] The nanocomposite materials can include a variety of nanoparticles. For example, the nanoparticles can be metal nanoparticles, metal oxide nanoparticles, metal halide (e.g., metal fluoride) nanoparticles, metal boride nanoparticles, metal phosphate nanoparticles, or combinations of such nanoparticles. The nanoparticles can include a variety of metals. The nanoparticles can have multiple metals (e.g., metal alloys and mixed metal oxides). In the case of multiple metals in the nanoparticles, depending on the composition the individual nanoparticles can have mixed composition (alloyed nanoparticles) or a mixture of nanoparticles with different composition. For example, Feo 75Mno 250 can provide alloyed nanoparticles and Sn/FeSn2 can provide a mixture of nanoparticles with different compositions. The nanoparticles can be crystalline or amorphous.
[0068] Examples of suitable metal nanoparticles include Fe, Mn, and FeSn2, FeNi3, Al, Sn, Ge, and Si. Examples of suitable metal oxides include Fe203 (e.g., 7-Fe203), Fe304, Mn203, M-Mn204 (M = Li, Na, K), M003, V205, T102, M4T15012 (M = Li, Na, K, Ag), Sn02, SnO, Co304, and MCo02 (M = Li, Na, K). Examples of suitable metal sulfides include MoS2, MoS3 FeS2, FeS, Fei,S(x=0-0.2), CoS, CuS, Cu2S, TiS2, and M2S (M = Li, Na, K).
Examples of suitable metal borides include TiB2, VB2, and LiBio. Examples of a suitable metals fluoride are CuF2, FeF2, and FeF3. Examples of suitable metal phosphates include MFePat (M=Li, Na, K) and LiMnxFei,PO4.
[0069] The nanoparticles are present at 10 % by weight to 90 % by weight, including all integer % by weight values and ranges therebetween. In an example, the nanoparticles are present at 40 % by weight to 90 % by weight.
[0070] Based on the composition of the nanoparticles and the methods used to form the nanoparticles, the nanoparticles can have a variety of shapes and sizes.
In various examples, the nanoparticles have a spherical shape (e.g., Fe203 nanoparticles) or a rectangular shape (e.g., MoS2 nanoparticles). In the case of spherical nanoparticles, the diameter of the nanoparticles is from 5 nm to 500 nm, including all integer nanometer values and ranges therebetween, in size. In the case of rectangular nanoparticles, the nanoparticles have a length of 20 to 100 nm, including all integer nanometer values and ranges therebetween, and a thickness of 5 to 20 nm, including all integer nanometer values and ranges therebetween. The size can be an average size. For example, the size of individual nanoparticles and the average nanoparticle size can be measured by transmission electron microscopy.
[0071] The nanoparticles have a narrow size distribution. For example, the nanoparticles have a polydispersity index of 1.001 to 1.05, including all values to 0.001 and ranges therebetween. In an embodiment, the nanoparticles are monodisperse (i.e., the fraction of nanoparticles within one standard deviation from the number average size is greater than or equal to 75%). In another embodiment, the fraction of nanoparticles within one standard deviation from the number average size is greater than or equal to 90%.
[0072] The nanoparticles are embedded in a carbon matrix. The carbon matrix is a partially graphitic or graphitic material. The graphitic material is a material consisting of graphite. The partially graphitic material is a material comprising graphite that may also contain disordered graphitic lattices and/or amorphous carbon. The presence of graphite, disordered graphitic lattices and/or amorphous carbon can be determined by techniques such as, for example, XRD and Raman spectroscopy. The carbon matrix is porous and amorphous.
Aggregation of the nanoparticles in the carbon matrix is not observed (e.g., by TEM, SEM, or as described herein.
[0073] The carbon matrix can have a range of porosity based the materials and conditions used to form the matrix. In various examples, the pores of the carbon matrix are less than 100nm, less than 20nm, or less than 5nm.
[0074] The nanocomposite materials exhibit desirable properties. The nanocomposite material is conductive. The material can have a conductivity of 10-5 to 100 S/cm. The material can have a Vickers Hardness of the composite is 1 to 40 GPa. The material can have a fracture toughness of the composite is 5 to 25 MPa 111112. In various examples, the capacity retentions of the composites in lithium-ion batteries is greater than 90%, greater than 95%, greater than 98% in 100 cycles at a 1C charge/discharge rate.
[0075] In an aspect, the present invention provides methods of forming a material.
The material can be a hybrid material or nanocomposite material as described herein. In an embodiment, the hybrid material is made by a method described herein. In an embodiment, the nanocomposite material is made by a method described herein.
[0076] In an embodiment, the method for forming a material comprises the steps of:
contacting one or more monomers, one or more metal precursor compounds, optionally, an initiator, and, optionally, one or more solvents to form a reaction mixture, heating the reaction mixture such that a hybrid material comprising a plurality of metal precursor compounds chemically bonded to the polymer matrix is formed and, optionally, isolating the hybrid material.
[0077] In an embodiment, the reaction mixture comprises: a first (e.g., bulk) monomer (e.g., acrylonitrile), optionally, a second (vinyl or cross-linking) monomer (e.g., divinyl benzene), a metal precursor compound (metal carboxylate) (e.g., iron undecylenate), an initiator (e.g., AIBN), a (anionic) surfactant (e.g., sodium dodecyl sulfate), water, and one or more organic solvents such that a reaction mixture that is an aqueous emulsion is formed.
In this embodiment, the reaction mixture is, optionally, subjected to high-shear mixing such that a miniemulsion having oil-in-water droplets with an average size of 0.01 microns to 0.5 microns if formed. For example, high shear mixing (for bench-top scale synthesis) can be provided by a sonication horn operated at 500W and at 20kHz with 50%
amplitude. A larger scale reaction may require higher power to achieve the desired shear.
[0078] In another embodiment, the reaction mixture comprises: a first (e.g., bulk) monomer (e.g., resorcinol), and, optionally, a second (bulk) monomer (e.g., formaldehyde), a metal precursor compound (e.g., ammonium tetrathiomolybdate), and water.
or four) of metal precursors, where the metal precursors each comprise a different metal.
[0080] The hybrid material can be pyrolysed to form a nanocomposite material.
Nanoparticles are formed in situ from the metal precursor compounds as a result of the pyrolysis process. The pyrolysis process can be carried out in a single step or can have multiple steps. For example, carbonization can comprise consecutive, stabilization, carbonization, and graphitization steps. The determination of pyrolysis conditions is material dependent and is within the purview of one having skill in the art. For example, a single step pyrolysis step can be from 500 to 900 C, including all values to the degree Celsius and ranges therebetween. For example, a multiple step pyrolysis can be 320 C for lhour for stabilization and 500 C for 2hrs for carbonization. Higher temperatures may be required for complete graphitization.
[0081] The pyrolysis step (or one of the steps of a multiple step pyrolysis) can be carried out in an atmosphere comprising a variety of gases. A mixture of gases can be used.
For example, the pyrolysis step can be carried out in air (or an oxygen containing atmosphere) or an inert atmosphere (e.g., a nitrogen atmosphere, an argon atmosphere, or a mixture thereof). For example, a reactive gas such as carbon dioxide (an oxidizing gas) can be used to provide increased mesopore and micropore content of the carbon matrix relative to pyrolysis in the absence of such gas.
[0082] In an embodiment, the method further comprises the step of pyrolysing the hybrid material, such that a nanocomposite material comprising a plurality of metal oxide nanoparticles (or metal nanoparticles) embedded in a carbon matrix is formed.
[0083] In an embodiment, the resorcinol-formaldehyde hybrid polymers are pyrolysed in an atmosphere comprising carbon dioxide or in a carbon dioxide gas atmosphere. The carbon dioxide is present at atmospheric pressure or substantially atmospheric pressure. The use of carbon dioxide in the pyrolysis step can provide a carbon matrix having a desirable morphology. For example, the carbon matrix can have an interconnected pore structure and higher surface area than materials obtained without using carbon dioxide in the pyrolysis step. For example, pyrolysis of a resorcinol-formaldehyde hybrid polymer at 800 C in a CO2(g) atmosphere provides carbon with broad pore size distribution (including mesopores and micropores) with graphene-like sheet textures. Using carbon dioxide in the pyrolysis step can result in a loss of mass in the resulting composite material and increases the interconnectivity of the pores of the carbon matrix.
The nanoparticles of the starting nanocomposite are subjected to reaction conditions that result in formation of a portion of or all nanoparticles having a different chemical composition than the starting nanoparticles. For example, metal oxide nanoparticles are reacted such that metal, metal halide, metal sulfide, and metal phosphate nanoparticles are formed or metal sulfide nanoparticles are reacted such that metal oxides, metal halide, metal, or metal phosphate nanoparticles are formed.
[0085] In an embodiment, the method further comprises reducing the metal oxide nanoparticles of the nanocomposite material comprising a plurality of metal oxide nanoparticles embedded in a carbon matrix by contacting the nanocomposite material with a reductant (e.g., hydrogen gas) or heating the nanocomposite material under inert conditions (to a temperature higher than the carbonization temperature (carbon serves as the reductant)), such that a nanocomposite material comprising a plurality of metal nanoparticles embedded in a carbon matrix is formed.
[0086] In an embodiment, the method further comprises contacting the nanocomposite material comprising a plurality of metal oxide nanoparticles embedded in a carbon matrix with a sulfur compound (e.g., sulfur), halide compound (e.g., fluoride compound), or phosphate compound, such that a nanocomposite material comprising a plurality of metal sulfide, metal halide, or metal phosphate nanoparticles embedded in a carbon matrix is formed.
[0087] In an embodiment, the method further comprises reducing the metal sulfide nanoparticles of the nanocomposite material comprising a plurality of metal sulfide nanoparticles embedded in a carbon matrix by contacting the nanocomposite material with a reductant (e.g., hydrogen gas) or heating the nanocomposite material under inert conditions (to a temperature higher than the carbonization temperature (carbon serves as the reductant)), such that a nanocomposite material comprising a plurality of metal nanoparticles embedded in a carbon matrix is formed.
[0088] In an embodiment, the method further comprises contacting the nanocomposite material comprising a plurality of metal sulfide nanoparticles embedded in a carbon matrix with an oxygen compound, halide compound, or phosphate compound, such that a nanocomposite material comprising a plurality of metal oxide, metal halide, or metal phosphate nanoparticles embedded in a carbon matrix is formed.
hybrid material. Examples of suitable bulk monomers include acrylonitrile, resorcinol, formaldehyde, vinylpyrrolidone, vinyl alcohol, acrylic acid, and phenol.
[0090] The cross-linking monomer forms cross links in the polymer.
Examples of suitable cross-linking monomers include divinylbenzene, 1,4-butadiene, isoprene, vinylsilane, and sulfur.
[0091] Any initiator that initiates the polymerization of the monomers can be used.
For example radical polymerization initiators can be used. Examples of suitable initiators include 2,2'-azobisbutyronitrile (AIBN), benzoyl peroxide, dicumyl peroxide, potassium persulfate, and 4,4' -azobis(4-cyanov aleric acid).
[0092] Any surfactant that forms a suitable aqueous emulsion can be used. For example anionic surfactants can be used. Examples of suitable surfactants include sodium dodecyl sulfate, hexadecyltrimethylammonium bromide, and polysorbates.
[0093] A single solvent or mixture of solvents can be used. For example, the solvent can be water. In the case where water is a solvent, depending on, for example, the components of the reaction mixture, it may be desirable to have the pH of the reaction mixture be greater than 7. Examples of suitable solvents include water, toluene, and cyclohexane.
[0094] The selection of reaction conditions that result in formation of the desired nanoparticle composition is within the purview of one having skill in the art.
The polymerization temperature for acrylonitrile is typically 60-80 C.
[0095] The steps of the method described in the various embodiments and examples disclosed herein are sufficient to produce hybrid materials and/or nanocomposite materials of the present invention. Thus, in an embodiment, the method consists essentially of a combination of the steps of the methods disclosed herein. In another embodiment, the method consists of such steps.
[0096] In an aspect, the present invention provides devices comprising the hybrid material or nanocomposite materials described herein. Examples of such devices include batteries (e.g., secondary batteries), on-chip inductors. Such device structures and methods of making such structures are known in the art.
[0097] In an embodiment, the present invention provides an electrode comprising a nanocomposite material. In an embodiment, a device comprises an electrode (e.g., an anode) comprising the nanocomposite material. In an embodiment, the present invention provides an on-chip inductor comprising the nanocomposite material. In an embodiment, a device nanocomposites containing iron or iron/nickel alloy nanoparticles.
[0098] The following examples are presented to illustrate the present invention. They are not intended to limiting in any manner.
[0099] This example describes the synthesis and characterization of examples of hybrid materials and nanocomposite materials of the present invention.
[0100] An in situ, scalable method for creating a variety of transition metal oxide¨
carbon nanocomposites was developed based on free-radical polymerization and cross-linking of poly(acrylonitrile) in the presence of the metal oxide precursor containing vinyl groups. The approach yields a cross-linked polymer network, which uniformly incorporates nanometer-sized transition metal oxide particles. Thermal treatment of the organic¨inorganic hybrid material produces nearly monodisperse metal oxide nanoparticles uniformly embedded in a porous carbon matrix. Cyclic voltammetry and galvanostatic cycling electrochemical measurements in a lithium half-cell are used to evaluate the electrochemical properties of a Fe304¨carbon composite created using this approach. These measurements reveal that when used as the anode in a lithium battery, the material exhibits stable cycling performance at both low and high current densities. The polymer/nanoparticle copolymerization approach can be readily adapted to synthesize metal oxide/carbon nanocomposites based on different particle chemistries for applications in both the anode and cathode of LIBs.
[0101] A facile, scalable emulsion polymerization technique for synthesizing transition metal oxide nanoparticles embedded in a porous carbon matrix has been reported.
The method (illustrated in Figure 1) relies upon co-polymerization and cross-linking of the carbon precursor (acrylonitrile) and the nanoparticle precursor in a single-step; it yields polymer¨nanoparticle hybrids with uniform particle distributions at high nanoparticle loadings. The procedure is also applicable for large-scale production of metal oxide¨carbon composites required for commercial-scale LIB manufacturing processes. The procedure was demonstrated by using a high-capacity (924 mA h g-1) transition metal oxide (Fe304) and show that it is adaptable to other oxides.
[0102] A nanocomposite of metal oxide/metal and carbon has been synthesized via a polymerization-carbonization process. A metal precursor (a carboxylic acid salt of the metal), soluble in nonpolar solvents, is mixed with a monomer, a cross-linking agent and a surfactant yield a composite of polymer nanoparticles encapsulating the iron precursor.
The material is then separated from the liquid phase and carbonized to give a composite material of metal oxide/metal-carbon nanoparticles, which may be used as the active electrode material for -- lithium-ion batteries. Fe304 was demonstrated as an example compound but the method is applicable to various metal oxides/metals. The method can also be extended to synthesize nanocomposites consisting of nanoparticles of other materials (e.g., other compounds which contain the metal such as CoS or a metal fluoride such as CuF2) embedded in a carbon matrix, through ex situ treatment of metal/carbon composites with sulfur, fluorine, and other -- materials (see, e.g., Example 2).
[0103] Reagents used in the study were purchased from Sigma-Aldrich unless otherwise specified and used without purification. Iron undecylenate was synthesized by the following procedure. 10.8 g (40 mmol) of FeC13=6H20, 4.8 g (0.12 mol) of NaOH
and 22.1 g (0.12 mol) of undecylenic acid were added to a mixture of 80 ml of ethanol, 60 ml of water -- and 140 ml of hexane under vigorous stifling. The mixture was heated at 70 C for 3 hours and then the organic phase was collected using a separation funnel. After washing with water for 3 times, hexane was driven off from the mixture using a rotary evaporator to obtain iron undecylenate, a waxy solid.
[0104] In a typical reaction, 2 ml acrylonitrile (AN), 2 ml divinylbenzene (DVB) and -- 1.8 g of iron undecylenate were mixed to form a homogeneous solution. 3 mg of azobisisobutyronitrile (AIBN) and 100 mg sodium dodecyl sulfate (SDS) were added to 25 ml of water and the former solution introduced into the aqueous phase under sonication with a Sonics VCX500 horn (500 W, 20 kHz, amplitude 50%). The mixture was sonicated for 3 minutes and after a stable emulsion was formed, heated at 70 C for 12 h.
Sodium chloride -- was added to induce aggregation of the resultant polymer¨inorganic hybrid particles, which were collected by centrifugation. The material obtained was heated in a nitrogen atmosphere, first to 320 C, held at this temperature for 1 h, then to 500 C and held for 2 h to obtain the final metal-oxide/carbon nanocomposite product.
[0105] The crystal structures of the particles were characterized using a Scintag Theta¨theta PAD-X X-ray Diffractometer (Cu Ka, ) = 1.5406 A) and their morphologies were studied using an FEI Tecnai G2 T12 Spirit Transmission Electron Microscope (120 kV).
Raman spectra were taken using a Renishaw In Via Confocal Raman Microscope.
Thermogravimetric analysis was performed using a TA Instruments Q5000 IR
Thermogravimetric Analyzer. Electrical conductivity measurement was made using a Lucas cm'. Gas adsorption analysis for porous materials was performed using a Micromeritics ASAP 2020 Accelerated Surface Area and Porosimetry System.
[0106] Electrochemical characterization of the composites as anode materials in rechargeable lithium-ion batteries was performed at room temperature in homemade Swagelok-type cells. The working electrode consists of 80 wt% of the active material, 10 wt% of carbon black (Super-P Li from TIMCAL) as a conductivity aid, and 10 wt%
of polymer binder (PVDF, polyvinylidene fluoride, Aldrich). Lithium foil was used as the counter and reference electrodes. A 1 M solution of LiPF6 in a 50 : 50, w/w mixture of ethylene carbonate and diethyl carbonate was used as the electrolyte. Celgard polypropylene membranes are used as the separator. Assembly of cell was performed in a glove box with moisture and oxygen concentrations below 1 ppm. The room-temperature electrode capacities were measured using Neware CT-3008 battery testers.
[0107] Powder X-ray diffraction was performed to determine the crystalline phase of the transition metal oxide. The XRD results, shown in Figure 2(a), match well with those of magnetite (JCPDS card no. 19-629). The broad signal in the range of 20-30 may be due to the presence of non-crystalline carbon in the composite, because the most intense reflection for graphitic carbon (002 layer) should appear at 26.8 . From the ScheiTer's formula, the average crystallite size of the Fe304 phase is found to be 21 nm.
[0108] Transmission Electron Micrographs (TEM) for the polymer¨particle complex are shown in Figure 3(a). The material generally consists of particles with sizes in the range 200-400 nm aggregated together. Energy Dispersive X-Ray Spectroscopy (EDX) was performed on the complex, as shown in Figure 3(c), which confirms that iron has been successfully incorporated in the complex. The morphology of the material after calcination is shown in Figure 3(b). It consists of uniformly sized Fe304 nanoparticles embedded in a carbon matrix and the size is consistent with the average crystallite size calculated from the X-Ray diffractograms (21 nm). Oxidative thermal gravimetric analysis (TGA) may be used to measure the weight fraction of active material Fe304 in the composite and the data are shown in Figure 3(d). The material is heated to 700 C under air so that Fe304 is oxidized to Fe203 and carbon is oxidized to CO2. From the remaining weight (of Fe203), the original weight fraction of Fe304 is calculated to be 66%.
[0109] Other carboxylic acid salts of iron have been used as the precursor, for example iron oleate, but the amount of Fe304 eventually encapsulated in the product can be substantially lower (e.g., 33%) than for iron undecylenate. The higher molecular weight of efficient incorporation in the polymer complex. In addition, the fractional weight loss of conversion of Fe(ole)3 to Fe304 (91%) is larger than conversion of Fe(ole)3 to Fe304 (87%), because of the larger molecular weight of Fe(ole)3. Iron(III) acetylacetonate (Fe(acac)3), which has a lower molecular weight than Fe(undec)3 was also investigated. In this case, the higher water solubility of the particle precursor does not allow formation of stable micelles required for emulsion polymerization.
[0110] Polyacrylonitrile is frequently used to synthesize graphitic materials through calcination at high temperatures. To obtain highly graphitic carbon, PAN
should be subjected to three consecutive processes, namely, stabilization, carbonization and graphitization. In the stabilization step, PAN is heated to 200-300 C in air and converted to a cyclic or a ladder compound, followed by treatment in nitrogen atmosphere to about 1000 C to achieve carbonization of the material. The third step, known as graphitization, is to heat the material to 1500-3000 C under argon atmosphere to improve the ordering and orientation of the crystallites. Because the present system contains metal oxides, if the material is heated to temperatures above ¨ 700 C for the sake of increasing the graphite content in the product, there is the possibility of carbon reducing the metal oxide to pure metal. As a compromise, a carbonization protocol requiring heating the material at 500 C in dry N2 was used.
[0111] The Raman spectrum of the Fe304¨C composite is shown in Figure 4. It is immediately noticeable that the spectrum contains two prominent peaks at around 1350 and 1590 wavenumbers. Raman spectra for carbon materials usually contain several peaks. In particular, the spectrum can be deconvoluted to five bands, conesponding to ideal graphite (G 1580 cm-1), a disordered graphitic lattice (D1 1350 cm-1, D2 1620 cm-1 and cm 1), or amorphous carbon (D3 1500 cm 1). G and D2 both come from sp2 carbon vibrations, which can be difficult to distinguish, and in some works have been treated as one single component in the fitting procedure. Lorentzian functions were used in the fitting and the calculated positions for the peaks are: G 1596 cm-1, D1 1349 cm-1, D3 1471 cm-1, and D4 1230 cm-1. This analysis indicates the carbon obtained in the composite is partially graphitic.
[0112] Magnetite has the formula Fe2 [Fe3+2104 and adopts an inverse spinet structure. In each unit cell (containing 8 multiples of Fe304), 8 out of 16 Fe3+ ions occupy 8 out of the 64 tetrahedral sites and all the Fe2+ ions and the remaining 8 Fe3+
ions are distributed in 16 out of 32 octahedral sites. Lithiation of Fe304 follows the following pathway:
" -(Piev JO., (Maw 13 IrePizaw 2) _________________________________ 3t41...0 =4=3re (Maw 3) [0113] Here parentheses denote ions in tetrahedral sites and square brackets denote ions in octahedral sites. During the insertion of up to 1.0 Li, the Li + ions fill up octahedral vacancies, with Fe3+ in the tetrahedral sites displaced to octahedral sites, leading to the formation of a rock-salt-like structure of Li1.0Fe304 at the end of this step.
Further insertion of lithium involves the filling of the tetrahedral sites by Li + ions. Metallic iron is extruded from the rock-salt structure to accommodate the incoming Li + ions.
[0114] Cyclic voltammograms for Fe304¨C composites are shown in Figure 5(a) (scan rate = 0.2 mV s-1). The patterns are consistent with the CV results from other reports on Fe304¨C composites. In the anodic process, starting from the second cycle, the lithium intercalation occurs mainly at around 0.7 V and in the cathodic process the oxidation of Fe occurs at around 1.8 V. In the first cycle, the intercalation occurred at a lower voltage of around 0.4 V, probably because of an overpotential arising from the crystal structure changes from the inverse spinet structure to the rock salt type structure. The voltage¨capacity profiles for the complex cycled at different charging rates (1 C or 0.5 C) are shown in Figure 5(b).
The lithium intercalation plateaus are not as flat for the Fe304 in carbon composites compared to the pure oxide, probably because of reduction in crystallinity and/or change in surface site energetics during the process of the carbon formation for the composite.
[0115] Cycling performance data for the Fe304¨C composites are shown in Figure 6.
The material was cycled at 1 C and 0.2 C, respectively for 100 cycles and the performance under different charging rates ranging from 0.5 C to 5 C was also studied.
The capacities are calculated based on the metal oxide mass because the capacity¨voltage profiles do not indicate significant contribution from lithium intercalation into the carbon host. It is apparent from Figure 6 that the composites show very stable performance and little fading for 100 cycles, even at 1 C charging rate. The performance is also stable for higher charging rates (20 cycles are shown as examples). The performance of bare Fe304 nanoparticles (50 nm in size, commercially available from Alfa Aesar) as the anode material is also shown in Figure 6(d) for comparison purposes; the clear improvements provided by the composite materials are visible from this plot. The performance of pure carbon made from pyrolysis of PAN¨DVB at to the lithium storage capacity.
[0116] The stable electrochemical performance of the Fe304-C
nanocomposites can be attributed to different features of the materials. Considering the relatively low electronic conductivity of the carbon component, it is not a consequence of enhanced electronic transport afforded by the carbon. The uniformly sized Fe304 nanoparticles are embedded in the carbon matrix, which might serve to alleviate the volume change incurred during the repeated cycling. A porous, mechanically flexible reinforcement that allows good penetration by the electrolyte into the active material is therefore considered advantageous. Nitrogen adsorption analysis was performed on the composite and the surface area measured by the BET method is 122 m2 g-1, with the isotherms and the pore size distribution for the composite (calculated using BJH method) shown in Figure 7. The BET surface area of pure carbon obtained from pyrolysis of the PAN-DVB polymer (without Fe304 nanoparticles) is about three times higher, 369 m2 g-1. The pore size distribution results show that most of the pores are less than 10 nm in size.
[0117] The size of the Fe304 nanoparticles also seems to be an important factor in determining the electrochemical performance. Average diameters of Fe304 particles synthesized using hydrothermal/solvothermal methods are usually greater than 150 nm because the particles are typically aggregates of smaller primary crystallites. In the current method, the size of the Fe304 nanoparticles is relatively small and the greater surface area and shorter diffusion length may allow easier access of the active material by the lithium ions.
[0118] The method developed for creating Fe304-C composites can be applied to synthesize nanocomposites of various other metal oxides (or other related materials such as pure metal) embedded in carbon matrices. Another interesting material is MnO, which has a theoretical lithium storage capacity of 755 mA h g-1. MnO undergoes conversion reaction in lithium-ion batteries: 2Li + MnO ¨> Mn + Li20 and upon lithium insertion, Mn grains <5 nm in size are formed. MnO-C composites can be synthesized using manganese(II) undecylenate as the precursor. Figure 8(a) shows the X-ray diffractogram for the MnO-C
composite, which matches well with MnO (JCPDS card no. 07-230). Again a broad band is observed in the range of 20-30 , but no sharp peak could be found at 26.8 , indicating that the carbon component is largely amorphous. TGA is used to determine the fraction of MnO
in the composite. Upon heating to 700 C in air, MnO is oxidized to Mn203 and the weight fraction of MnO in the composite is calculated to be 58% assuming all the remaining material is case of Fe304, MnO nanoparticles embedded in a carbon matrix are obtained.
[0119] A typical cyclic voltammogram for the MnO¨C composite is shown in Figure 9(a) and lithium insertion/Mn2+ reduction seems to occur at around 0.5 V
against Li/Lit, which is consistent with previous reports on MnO anode materials.
Voltage¨capacity curves at 0.5 C and 1 C charging rates are shown in Figure 9(b) and cycling data for the composite run at 1 C and 0.2 C, and at varied charging rates are shown in Figure 9(c).
Similar to what was observed for the Fe304¨C composite, little capacity fade is observed even when the material is subject to 1 C charging rate for over >100 cycles. Cycling at higher charging rates is also seen to give stable performance. Therefore a prominent feature of the current protocol is the ability to yield materials with stable performance at moderately high charging rates.
[0120] In conclusion, a one-step free-radical polymerization method is used to synthesize cross-linked metal-oxide/poly(acrylonitrile) nanocomposites.
Pyrolysis of the composite at moderate temperatures in an inert atmosphere yields metal-oxide/carbon particles comprised of uniformly distributed metal oxide nanoparticles in a partially graphitic, but poorly conducting carbon host. The versatility of the approach has been demonstrated using two different metal oxides, Fe304 and MnO. When evaluated as anode materials in lithium-ion batteries, composites of both materials display stable performance at low and high cun-ent densities.
[0121] This example describes the synthesis and characterization of examples of hybrid materials and nanocomposite materials of the present invention.
[0122] Synthesis of LiFePO4@C nanocomposite. 108mg Li0H, 221mg H3PO4 and 660mg L-ascorbic acid are dissolved in 10m1 DI water, to which 116mg Fe304@C
nanocomposite powder is added. The solution is loaded into a pressurized container and heated at 270 C for 12hr. The powder obtained is centrifuged and washed with water.
[0123] Synthesis of Mn075Fe0250@C nanocomposite. Manganese (II) undecylenate is synthesized using the same method as iron (III) undecylenate, with MnC12 as the Mn precursor. 1.58g manganese (II) undecylenate and 0.75g iron (III) undecylenate are mixed to form a homogeneous mixture, and polymerization with acrylonitrile and divinylbenzene is performed using the same method as used for iron (III) undecylenate alone. The polymerization product is collected ant heat treated in the same way to obtain Mno 75Fe0 250@ C nanocomposite.
H3PO4 and 49mg H3P03 are dissolved in 10m1 DI water, to which 142mg Mn075Fe0250@C
nanocomposite powder is added. The solution is loaded into a pressurized container and heated at 270 C for 12hr. The powder obtained is centrifuged and washed with water.
[0125] The synthesis, structural characterization and electrochemical performance of MoS2¨carbon nanostructures is described in this example.
[0126] Composites of MoS2 and amorphous carbon were grown and self-assembled into hierarchical nanostructures via a hydrothermal method. Application of the composites as high-energy electrodes for rechargeable lithium-ion batteries was investigated. The critical roles of nanostructuring of MoS2 and carbon composition on lithium-ion battery performance are described. Pure MoS2 and 22 wt% carbon containing MoS2 materials are designated as MS-0 and MS-22 respectively.
[0127] Morphological investigations using SEM (Figure 18a) reveal that the product obtained via the hydrothermal treatment of the molybdenum sol in presence of carbon precursors (resorcinol and formaldehyde) takes the form of open structure of MoS2 and carbon. The TEM images of MS-22 (22 wt% carbon), as shown in Figures 18b and c, indicate that MoS2 in the composites are in the form of stacked nanosheets homogeneously embedded in a very thin matrix of amorphous carbon. The length and thickness of MoS2 nanosheets are about 40 and 10 nm respectively (inset of Figure 18b). It can be observed that the MoS2 sheets are composed of few MoS2 layers (-6 to 10 layers). A schematic of the in situ synthesis of MoS2¨carbon composites is shown in Figure 19A. In absence of resorcinol and formaldehyde, the MoS2 particles aggregate to form large MoS2 lumps (Figure 19B) as verified by the SEM and TEM images (Figures 18d and f). On the other hand, polycondensation of resorcinol with formaldehyde takes place during the hydrothermal process forming low density carbon gels. The MoS2 particles in the form of layers simultaneously crystallize during the hydrothermal process and are eventually uniformly dispersed in the carbon gel. The successive restacking of MoS2 layers is significantly inhibited by the carbon gel resulting in few layers of MoS2 nanosheet and consequently self-assembled in interconnected flakes resulting in three dimensional MoS2¨carbon nanostructures.
[0128] The X-ray diffraction patterns (XRD) of the MS-0 and MS-22 shows broad diffraction peaks which can be indexed to 2H polytype of MoS2 crystal structure with space composites, no peak shifts are observed suggesting that the MoS2 crystallites are unconstrained by chemical bonding to the carbon framework. Furthermore, no characteristic peak from graphitic carbon was detected in the XRD, indicating the formation of amorphous carbon. It can be observed that the intensity of (002) peak for MS-22 is relatively lower compared to pure MoS2 particles (see ESI, Figure 23). The peak at (002) is typically observed in bulk analogue. It suggests that the carbon inhibits the growth of (002) planes of MoS2 crystallites, which confines its growth in the plane favoring formation of few-layer nanosheets in the amorphous carbon matrix. The carbon content is estimated using thermogravimetric analysis; the results are depicted in (see ESI, Figure 24).
It is seen that there is successful incorporation of 11, 22, 32 and 41 wt% of carbon in MoS2-carbon nanostructures. The BET surface areas of MS-0, MS-22 and MS-41 are 3, 35 and 157 m2 g-1 respectively (see ESI, Figure 25). The increase in surface area with increasing carbon content is attributed to the porous nature of amorphous carbon.
[0129] The electrochemical properties and lithium battery performance of all MoS2-carbon composites using galvanostatic discharge and cyclic voltammetry measurements was investigated. Electrodes were prepared from the MoS2-carbon composites and a PVDf binder, i. e. , no carbon black or other conductivity aid was added. Figure 20 shows the galvanostatic charge (Li removal)/discharge (Li insertion) profiles obtained from pure and carbon-composited MoS2 at room temperature (25 C) and at a constant current density of 100 mA g-1 in the voltage range of 0.05-3 V. In the present study, pure MoS2 particle exhibited a discharge capacity of 2362 mA h g-1 in the Et discharge cycle (Figure 20a). Two potential plateaus at 1.1 V and 0.61 V corresponding to the formation of LixMoS2 and conversion of MoS2 to Mo respectively are also readily apparent from Figure 20. The pure MoS2 shows very poor Et charge and 2nd discharge capacities of 247 and 53 mA h g-1, respectively without any noticeable potential plateaus.
[0130] The MoS2-carbon nanocomposite structures all exhibit significantly improved capacity retention (Figures 20b and e). All MoS2-carbon composites manifest the prominent characteristic discharge potential plateaus at 1.1 V and 0.6 V in the Et discharge cycle and charge potential plateau at 2.3 V in all charge cycles (Figure 20b). During subsequent discharge cycles, the potential plateau observed at 0.6 V disappeared with emergence of two new inconspicuous potential plateaus at -1.9 V and 1.2 V (Figure 20b) which is in agreement with previous observations. The first discharge capacities of MS-11, MS-22, MS-32 and MS-41 are 2108, 1462, 1130, and 1078 mA h g-1 with coulombic efficiencies of 79%, 62%, 63%,
- 22 -battery performance in terms of showing higher capacity and long-term stability. MS-22 shows a discharge capacity of 755 mA h g-1 with coulombic efficiencies of 98%
after 100th cycle at constant current density of 100 mA g-1. In contrast, MS-11, MS-32 and MS-41 show capacities of 10, 517 and 354 mA h g-1 after 100th cycle. Although MS-32 and MS-41 show good long-term capacity retention, the lower capacity possessed by both of them is due to higher amount of inactive carbon in the electrode compositions. It ascertains the importance of optimization of inactive carbon in electrode materials.
[0131] The improved cycling stability of Mo52¨carbon composites can be attributed to the inhibition of the side reaction of Li25 with the electrolyte that forms a thick, gel-like polymeric layer and manifests particle aggregation. The evidence in support of this explanation is provided by cyclic voltammetry (CV) (Figures 20c and d), ex situ XRD
(Figure 21) and SEM of the 1St cycledischarged product (Figure 21). The CV
plot of MS-22 (Figures 20d) shows two distinct reduction peaks at 0.93 V and 0.37 V in the 1St cycle, which is indicative of the respective formation of LixMoS2 and decomposition of Mo52 to Mo and Li25. In the subsequent oxidation cycles shown until the 15th cycle, small but sharp intensity peaks at 1.67 V and 2.34 V can be observed. These peaks are attributed to partial and complete oxidation of Mo to Mo52, respectively. In the subsequent reduction cycles, peaks at 0.93 V and 0.37 V disappear and two new small intensity peaks at 1.83 V and 1.01 V can be observed. The peaks are in agreement with the potential plateaus observed in charge¨
discharge curves of MS-22 (Figure 20b). It is also evident from the CV data that even after 15th cycle, the Mo52¨carbon composite material shows excellent electroactivity, with negligible decrease in peak intensities. On contrary, pure Mo52 shows a distinct reduction peak at 0.93 V and a broad reduction peak in the voltage range of 0.05-0.5 V
in the E1 reduction cycle. Two minor intensity oxidation peaks at 1.8 V and 2.3 V can also be observed in the 1St oxidationcycle followed by little noticeable electrochemical activity after the E1 cycle. The ex situ XRD of MS-0 and MS-22 both shows the signature of Mo (ICDD
no. 071-3771) and Li25 (ICDD no. 071-4841) after 1St discharge cycle (Figure 21).
However, the peak intensity of Li25 for MS-0 (Figure 21b) is significantly lower than MS-22 (Figure 21a). The breadth of the CV peak at 0.05-0.5 V and decrease in Li25 XRD peak intensity in case of pure Mo52 particle can be explained in terms of the side reaction of Li25 with the electrolyte.
Further evidence is provided by the ex situ SEM images of the 15t cycledischarge products of MS-0 (Fig. 21d) and MS-22 (Figure 21c). MS-22 maintains its original structure whereas pure Mo52 particles aggregated due to electrolyte degradation with Li25. As a consequence of
after 100th cycle at constant current density of 100 mA g-1. In contrast, MS-11, MS-32 and MS-41 show capacities of 10, 517 and 354 mA h g-1 after 100th cycle. Although MS-32 and MS-41 show good long-term capacity retention, the lower capacity possessed by both of them is due to higher amount of inactive carbon in the electrode compositions. It ascertains the importance of optimization of inactive carbon in electrode materials.
[0131] The improved cycling stability of Mo52¨carbon composites can be attributed to the inhibition of the side reaction of Li25 with the electrolyte that forms a thick, gel-like polymeric layer and manifests particle aggregation. The evidence in support of this explanation is provided by cyclic voltammetry (CV) (Figures 20c and d), ex situ XRD
(Figure 21) and SEM of the 1St cycledischarged product (Figure 21). The CV
plot of MS-22 (Figures 20d) shows two distinct reduction peaks at 0.93 V and 0.37 V in the 1St cycle, which is indicative of the respective formation of LixMoS2 and decomposition of Mo52 to Mo and Li25. In the subsequent oxidation cycles shown until the 15th cycle, small but sharp intensity peaks at 1.67 V and 2.34 V can be observed. These peaks are attributed to partial and complete oxidation of Mo to Mo52, respectively. In the subsequent reduction cycles, peaks at 0.93 V and 0.37 V disappear and two new small intensity peaks at 1.83 V and 1.01 V can be observed. The peaks are in agreement with the potential plateaus observed in charge¨
discharge curves of MS-22 (Figure 20b). It is also evident from the CV data that even after 15th cycle, the Mo52¨carbon composite material shows excellent electroactivity, with negligible decrease in peak intensities. On contrary, pure Mo52 shows a distinct reduction peak at 0.93 V and a broad reduction peak in the voltage range of 0.05-0.5 V
in the E1 reduction cycle. Two minor intensity oxidation peaks at 1.8 V and 2.3 V can also be observed in the 1St oxidationcycle followed by little noticeable electrochemical activity after the E1 cycle. The ex situ XRD of MS-0 and MS-22 both shows the signature of Mo (ICDD
no. 071-3771) and Li25 (ICDD no. 071-4841) after 1St discharge cycle (Figure 21).
However, the peak intensity of Li25 for MS-0 (Figure 21b) is significantly lower than MS-22 (Figure 21a). The breadth of the CV peak at 0.05-0.5 V and decrease in Li25 XRD peak intensity in case of pure Mo52 particle can be explained in terms of the side reaction of Li25 with the electrolyte.
Further evidence is provided by the ex situ SEM images of the 15t cycledischarge products of MS-0 (Fig. 21d) and MS-22 (Figure 21c). MS-22 maintains its original structure whereas pure Mo52 particles aggregated due to electrolyte degradation with Li25. As a consequence of
-23 -show higher capacity (2362 mA h g-1) but with extremely poor coulombic efficiency of 10%
compared to all carbon¨MoS2 composites. In addition, particle agglomeration is also a serious cause for the poor cyclability of pure MoS2.
41, MS-11 exhibits less stable storage capacity over extended cycling.
Evidently, carbon does have a stabilizing effect on the cycling stability of Mo52 and the composition of the composites can be used to influence their stability. Second, there is a critical concentration of carbon at which the capacity and cyclability are optimized. 22% carbon containing Mo52¨
carbon composite exhibits the best stability. It suggests that the optimum value of carbon in rendering stable cycle life is around 22%. At carbon concentrations less than 22%, the Mo52 particles are not effectively coated with carbon (ESI, Figure 26a) that promotes possible electrochemical reaction of Li25 and electrolyte during the first discharge process. It is important for lithium-ion battery purposes to ensure good buffering for active material.
Therefore, similar to MS-0, MS-11 shows higher first cycle discharge capacity (2108 mA h g-1) compared to other carbon¨Mo52 compositions. On the other hand, increasing carbon concentrations more than 22% results in thicker carbon coating (ESI, Figure 26b) and increase in inactive mass in the electrode. Since resorcinol¨formaldehyde synthesized carbon is porous, the electrolyte can wet the Mo52 particle. Therefore, MS-32 and MS-41 show stable electrochemical activity. However, the lithium storage capacities are lower than MS-22 due to increased proportion of inactive mass in the electrode.
[0133] The cycling stability and rate capability of MS-22 with additional carbon black in the electrode is shown in Figures 22 and 23 (ESI). It is observed that incorporation of higher amount (50%) of carbon black facilitates higher rate capability. To further testify the carbon quality present in the Mo52¨carbon composites, the material is calcined at 700 C.
The lithium battery performance is shown in (see ESI, Figure 28). Heat treatment of 700 C is found to have deteriorating effect on the cyclability due to possible temperature induced crystallite growth.
[0134] A facile one-pot hydrothermal method for the synthesis of Mo52¨carbon nanostructures with various carbon compositions was demonstrated. The procedure utilizes
compared to all carbon¨MoS2 composites. In addition, particle agglomeration is also a serious cause for the poor cyclability of pure MoS2.
41, MS-11 exhibits less stable storage capacity over extended cycling.
Evidently, carbon does have a stabilizing effect on the cycling stability of Mo52 and the composition of the composites can be used to influence their stability. Second, there is a critical concentration of carbon at which the capacity and cyclability are optimized. 22% carbon containing Mo52¨
carbon composite exhibits the best stability. It suggests that the optimum value of carbon in rendering stable cycle life is around 22%. At carbon concentrations less than 22%, the Mo52 particles are not effectively coated with carbon (ESI, Figure 26a) that promotes possible electrochemical reaction of Li25 and electrolyte during the first discharge process. It is important for lithium-ion battery purposes to ensure good buffering for active material.
Therefore, similar to MS-0, MS-11 shows higher first cycle discharge capacity (2108 mA h g-1) compared to other carbon¨Mo52 compositions. On the other hand, increasing carbon concentrations more than 22% results in thicker carbon coating (ESI, Figure 26b) and increase in inactive mass in the electrode. Since resorcinol¨formaldehyde synthesized carbon is porous, the electrolyte can wet the Mo52 particle. Therefore, MS-32 and MS-41 show stable electrochemical activity. However, the lithium storage capacities are lower than MS-22 due to increased proportion of inactive mass in the electrode.
[0133] The cycling stability and rate capability of MS-22 with additional carbon black in the electrode is shown in Figures 22 and 23 (ESI). It is observed that incorporation of higher amount (50%) of carbon black facilitates higher rate capability. To further testify the carbon quality present in the Mo52¨carbon composites, the material is calcined at 700 C.
The lithium battery performance is shown in (see ESI, Figure 28). Heat treatment of 700 C is found to have deteriorating effect on the cyclability due to possible temperature induced crystallite growth.
[0134] A facile one-pot hydrothermal method for the synthesis of Mo52¨carbon nanostructures with various carbon compositions was demonstrated. The procedure utilizes
- 24 -demonstrated that incorporation of carbon provides significantly improved cycling stability when the material is used as a lithium battery electrode. It is also found that an optimum level of carbon is required to produce materials with both high lithium storage capacity and good electrochemical cycling stability. The improved performance is attributed to following three main factors. First, the porous structure of the composites allows for facile Li + insertion¨
deinsertion into MoS2 nanosheets and for structural stresses induced by Li +
insertion¨
deinsertion to be properly accommodated since the dimension of MoS2 nanosheets are small (thickness ¨10 nm) and composed of few layers (-6 to 10 layers). Second, incorporation of Mo52 in the carbon matrix inhibits the side reaction of Li25 with electrolyte at the interface of Mo and carbon and finally, the carbon framework limits particle agglomeration.
The synthesis approach reported in the present invention will be beneficial for designing new organic-solvent free synthesis methods for creating composite electrode materials for lithium batteries.
[0135] Synthesis of Mo52-carbon: The Mo52-carbon composites with varying carbon weight fractions were synthesized by a hydrothermal method.
Resorcinol/formaldehyde (Sigma-Aldrich) and ammonium tetrathiomolybdate (Sigma-Aldrich) were used respectively as carbon and Mo52 precursors. A desired concentration (0.076 M) of aqueous solution of ammonium tetrathiomolybdate was added to another aqueous solution containing resorcinol, formaldehyde and sodium carbonate under continuous stiffing. The ratios of resorcinol to formaldehyde and to sodium carbonate were kept at 0.185 g m1-1 and 251 respectively calculated on a molar basis for all Mo52-carbon composites. However, the concentrations of resorcinol, formaldehyde and sodium carbonate were varied to obtain various carbon loadings in the final product. The intense violet color sol was transferred to a Teflon-lined stainless steel autoclave of capacity 100 ml (70% filling) and heated at 180 C for 12 hours and then cooled to room temperature. The resultant black product was recovered by centrifugation and washed with deionized water and freeze dried. The dried product was further calcined at 550 C for 4 hours in an atmosphere of 5% H2 balanced with Ar at a heating rate of 5 Cmin-1.
Pure Mo52 was synthesized by hydrothermal treatment of ammonium tetrathiomolybdate (180 C for 12 h, calcination at 550 C for 4 hours under H2/Ar), but without any addition of resorcinol and formaldehyde. The materials were designated as MS-0, MS-11, MS-22, MS-32 and MS-41coffesponding to 0, 11,22, 32 and 41 wt % of carbon in the Mo52-carbon composites.
deinsertion into MoS2 nanosheets and for structural stresses induced by Li +
insertion¨
deinsertion to be properly accommodated since the dimension of MoS2 nanosheets are small (thickness ¨10 nm) and composed of few layers (-6 to 10 layers). Second, incorporation of Mo52 in the carbon matrix inhibits the side reaction of Li25 with electrolyte at the interface of Mo and carbon and finally, the carbon framework limits particle agglomeration.
The synthesis approach reported in the present invention will be beneficial for designing new organic-solvent free synthesis methods for creating composite electrode materials for lithium batteries.
[0135] Synthesis of Mo52-carbon: The Mo52-carbon composites with varying carbon weight fractions were synthesized by a hydrothermal method.
Resorcinol/formaldehyde (Sigma-Aldrich) and ammonium tetrathiomolybdate (Sigma-Aldrich) were used respectively as carbon and Mo52 precursors. A desired concentration (0.076 M) of aqueous solution of ammonium tetrathiomolybdate was added to another aqueous solution containing resorcinol, formaldehyde and sodium carbonate under continuous stiffing. The ratios of resorcinol to formaldehyde and to sodium carbonate were kept at 0.185 g m1-1 and 251 respectively calculated on a molar basis for all Mo52-carbon composites. However, the concentrations of resorcinol, formaldehyde and sodium carbonate were varied to obtain various carbon loadings in the final product. The intense violet color sol was transferred to a Teflon-lined stainless steel autoclave of capacity 100 ml (70% filling) and heated at 180 C for 12 hours and then cooled to room temperature. The resultant black product was recovered by centrifugation and washed with deionized water and freeze dried. The dried product was further calcined at 550 C for 4 hours in an atmosphere of 5% H2 balanced with Ar at a heating rate of 5 Cmin-1.
Pure Mo52 was synthesized by hydrothermal treatment of ammonium tetrathiomolybdate (180 C for 12 h, calcination at 550 C for 4 hours under H2/Ar), but without any addition of resorcinol and formaldehyde. The materials were designated as MS-0, MS-11, MS-22, MS-32 and MS-41coffesponding to 0, 11,22, 32 and 41 wt % of carbon in the Mo52-carbon composites.
- 25 -diffraction (Scintag theta¨theta PAD-X-ray Diffractometer; Cu-Ka radiation, ii, = 1.5406 A).
The morphology was observed by scanning electron microscopy (SEM, LEO 1550 FESEM) and transmission electron microscopy (TEM, FEI Tecnai G2 T12). Specific surface area (BET) was obtained from nitrogen adsorption-desorption isotherms (Micromeritics ASAP
2020). Estimation of carbon content in Mo52-carbon composites was done using thermogravimetric analysis (TGA, TA Instruments Q5000). TGA experiments were performed by heating the sample in air from room temperature to 700 C at a heating rate of Cmin-1. For the working electrode, slurry of the active material and carbon black (Super P
10 Timacal) was prepared with PVdF (Sigma) in a weight ratio of Mo52:CB:PVDf = 90:0:10, 80:10:10, 65:10:10, 40:50:10 in N-methyl-pyrrolidone (NMP). The slurry was cast on a copper foil and dried in vacuum at 120 C for 12 h. Room temperature cyclic voltammetry (CV, CH608 CH Instruments) and galvanostatic charge/discharge cycling (Maccor) were done in 2032 coin-type cells with pure metal Li (Aldrich) as anode, Whatman glass fibre as separator and 1M LiPF6 in ethylene carbonate (EC, Aldrich) and dimethyl carbonate (DMC, Aldrich) (1:1 w/w) as an electrolyte.
[0137] This example describes the synthesis and characterization of examples of hybrid materials and nanocomposite materials of the present invention.
materials, nanoscale organic-inorganic hybrid materials created using the approach are attractive as anodes and cathodes for next-generation lithium and other rechargeable battery systems. Additionally, the platform is very versatile and through ex situ conversion or utilization of multiple precursors, can be applied to various classes of materials including metal oxides, metals, metal sulfides and alloys. The approach also lends itself to the development of scalable processes for production of nanostructured battery materials.
[0139] This general approach for synthesizing metal oxide-, metal sulfide-, and metal alloy-carbon nanocomposites ameliorates the physical and chemical stresses associated with repeated insertion and de-insertion of lithium present a fundamental challenge to further
The morphology was observed by scanning electron microscopy (SEM, LEO 1550 FESEM) and transmission electron microscopy (TEM, FEI Tecnai G2 T12). Specific surface area (BET) was obtained from nitrogen adsorption-desorption isotherms (Micromeritics ASAP
2020). Estimation of carbon content in Mo52-carbon composites was done using thermogravimetric analysis (TGA, TA Instruments Q5000). TGA experiments were performed by heating the sample in air from room temperature to 700 C at a heating rate of Cmin-1. For the working electrode, slurry of the active material and carbon black (Super P
10 Timacal) was prepared with PVdF (Sigma) in a weight ratio of Mo52:CB:PVDf = 90:0:10, 80:10:10, 65:10:10, 40:50:10 in N-methyl-pyrrolidone (NMP). The slurry was cast on a copper foil and dried in vacuum at 120 C for 12 h. Room temperature cyclic voltammetry (CV, CH608 CH Instruments) and galvanostatic charge/discharge cycling (Maccor) were done in 2032 coin-type cells with pure metal Li (Aldrich) as anode, Whatman glass fibre as separator and 1M LiPF6 in ethylene carbonate (EC, Aldrich) and dimethyl carbonate (DMC, Aldrich) (1:1 w/w) as an electrolyte.
[0137] This example describes the synthesis and characterization of examples of hybrid materials and nanocomposite materials of the present invention.
materials, nanoscale organic-inorganic hybrid materials created using the approach are attractive as anodes and cathodes for next-generation lithium and other rechargeable battery systems. Additionally, the platform is very versatile and through ex situ conversion or utilization of multiple precursors, can be applied to various classes of materials including metal oxides, metals, metal sulfides and alloys. The approach also lends itself to the development of scalable processes for production of nanostructured battery materials.
[0139] This general approach for synthesizing metal oxide-, metal sulfide-, and metal alloy-carbon nanocomposites ameliorates the physical and chemical stresses associated with repeated insertion and de-insertion of lithium present a fundamental challenge to further
- 26 -case investigated the nanocomposites manifest improved electrochemical stability whether they are applied as anodes or cathodes in a secondary battery.
[0140] An approach for the in situ synthesis of nanoparticles embedded in a carbon matrix through a miniemulsion polymerization technique was shown. The as prepared carbon-nanoparticle hybrid materials can be facilely modified ex situ to significantly increase the range of materials chemistries that can be achieved by the method. The approach is based on the in situ synthesis of inorganic nanoparticles and organic polymers from precursors capable of forming chemical cross-links with each other. After pyrolysis of the organic phase, the process yields a well-defined nanostructured material comprised of discrete inorganic nanoparticles embedded in a porous carbon matrix. Post treatment of the embedded particles creates carbon-nanoparticle hybrids based on metals, metal alloys, and a variety of other particles attractive for lithium battery applications.
[0141] Emulsion polymerization is a widely used method for synthesizing polymer latexes for applications such as adhesives and coatings. The method typically uses monomers with low water solubility, stabilized by surfactant in an aqueous media. The polymerization rate is limited by the diffusion of reactive monomer, through the aqueous phase, from monomer droplets to monomer-swollen polymer particles where polymerization takes place.
Application of high shear force to the emulsion yields a so-called miniemulsion, comprised of droplets with small sizes, usually 0.01-0.5 um, compared to 1-10 um in conventional emulsion polymerization. Because of the high surface area of monomer droplets in a miniemulsion, nucleation takes place mainly via radical entry into the emulsified monomer droplets and reaction proceeds through polymerization of the monomers in these small droplets. If more than one monomer chemistry is employed simultaneously or sequentially, the approach can be used to create copolymers with different architectures. If the polymerization reaction is performed in the presence of guest species miscible with the monomer (e.g. dyes, metal complexes, etc.), the guest species can be embedded in the polymer particle host. However, a common drawback is that only relatively low loadings (a few percent by weight) of the guest can be achieved. A new method to overcome this drawback and demonstrate the applicability of the method to synthesize composites involving various types of LIB electrode materials was demonstrated.
[0142] Chemicals and materials synthesis. Chemical reagents were purchased from Sigma-Aldrich and used without purification. Fe304@C nanocomposite was synthesized according to a previously reported procedure. 2m1 acrylonitrile (AN), 2m1 divinylbenzene
[0140] An approach for the in situ synthesis of nanoparticles embedded in a carbon matrix through a miniemulsion polymerization technique was shown. The as prepared carbon-nanoparticle hybrid materials can be facilely modified ex situ to significantly increase the range of materials chemistries that can be achieved by the method. The approach is based on the in situ synthesis of inorganic nanoparticles and organic polymers from precursors capable of forming chemical cross-links with each other. After pyrolysis of the organic phase, the process yields a well-defined nanostructured material comprised of discrete inorganic nanoparticles embedded in a porous carbon matrix. Post treatment of the embedded particles creates carbon-nanoparticle hybrids based on metals, metal alloys, and a variety of other particles attractive for lithium battery applications.
[0141] Emulsion polymerization is a widely used method for synthesizing polymer latexes for applications such as adhesives and coatings. The method typically uses monomers with low water solubility, stabilized by surfactant in an aqueous media. The polymerization rate is limited by the diffusion of reactive monomer, through the aqueous phase, from monomer droplets to monomer-swollen polymer particles where polymerization takes place.
Application of high shear force to the emulsion yields a so-called miniemulsion, comprised of droplets with small sizes, usually 0.01-0.5 um, compared to 1-10 um in conventional emulsion polymerization. Because of the high surface area of monomer droplets in a miniemulsion, nucleation takes place mainly via radical entry into the emulsified monomer droplets and reaction proceeds through polymerization of the monomers in these small droplets. If more than one monomer chemistry is employed simultaneously or sequentially, the approach can be used to create copolymers with different architectures. If the polymerization reaction is performed in the presence of guest species miscible with the monomer (e.g. dyes, metal complexes, etc.), the guest species can be embedded in the polymer particle host. However, a common drawback is that only relatively low loadings (a few percent by weight) of the guest can be achieved. A new method to overcome this drawback and demonstrate the applicability of the method to synthesize composites involving various types of LIB electrode materials was demonstrated.
[0142] Chemicals and materials synthesis. Chemical reagents were purchased from Sigma-Aldrich and used without purification. Fe304@C nanocomposite was synthesized according to a previously reported procedure. 2m1 acrylonitrile (AN), 2m1 divinylbenzene
-27 -azobisisobutyronitrile (AIBN) and 100mg sodium dodecyl sulfate (SDS) were added to 25m1 of water and the former solution added dropwise to the aqueous phase under sonication with a Sonics VCX500 horn (500W, 20kHz, amplitude 50%). The mixture was sonicated for 3 minutes and after a stable emulsion was formed, heated at 70 C for 12 hrs.
Sodium chloride was added to induce aggregation of the resultant polymer-inorganic hybrid particles, which were collected by centrifugation. The material obtained was heated in an argon atmosphere, first to 320 C, held at this temperature for lhr, then to 500 C and held for 2hrs to obtain the Fe304@C nanocomposite product. Fe304@C was then ground into powder and heated at 650 C in a tube furnace under a 7% H2 (balance Ar) gas environment for 2hrs to obtain Fe@C powders. The latter is mixed with 2x mass of sulfur, loaded into a Pyrex tube, sealed and heated at 500 C for 4hrs to obtain Fe52@C nanocomposite. The product is washed with CS2 to remove any residual elemental sulfur. To synthesize y-Fe203@C and a-Fe203@C
composites, Fe304@C powder is heated in air at 350 C for 5hrs and 390 C for lhr, respectively, to obtain the products. To synthesize V205@C, VC13 is used as the starting material to synthesize V(C10f119C00)3. After polymerizing with acrylonitrile, the material is pyrolysed at 500 C in argon for 2hrs and then heated in air at 390 C for lhourto obtain V205@C. To synthesize FeSn2@C nanocomposite, tin undecylenate (Sn(C10f119C00)2) was synthesized in a similar fashion as iron undecylenate, except with SnC12 as the starting material. 2.2g Fe(C10f119C00)3 and 1.8g Sn(C10f119C00)2 were mixed first, 2m1 AN and 2m1 DVB were added, and then the rest of the procedure was carried out as above.
[0143] The crystal structures of the particles were characterized using Scintag Theta-theta PAD-X X-Ray Diffractometer (Cu Ka, 2,= 1.5406 A) and their morphologies were studied using ELI Tecnai G2 T12 Spirit Transmission Electron Microscope (120kV).
Thermogravimetric analysis was performed using TA Instruments Q5000 IR
Thermogravimetric Analyzer.
[0144] Cell assembly and testing. Electrochemical characterization of the composites as anode materials in rechargeable lithium-ion batteries was performed at room temperature in 2032 coin-type cells. The working electrode consisted of 80 wt% of the active material, 10 wt% of carbon black (Super-P Li from TIMCAL) as a conductivity aid, and 10 wt%
of polymer binder (PVDF, polyvinylidene fluoride, Aldrich). Copper foil was used as the current collector for nanocomposites targeted for application as the LIB anode and aluminum for those targeted as cathodes. Lithium foil was used as the counter and reference electrode for evaluating both that anode and cathode materials. A 1 M solution of LiPF6 in a 50:50 w/w
Sodium chloride was added to induce aggregation of the resultant polymer-inorganic hybrid particles, which were collected by centrifugation. The material obtained was heated in an argon atmosphere, first to 320 C, held at this temperature for lhr, then to 500 C and held for 2hrs to obtain the Fe304@C nanocomposite product. Fe304@C was then ground into powder and heated at 650 C in a tube furnace under a 7% H2 (balance Ar) gas environment for 2hrs to obtain Fe@C powders. The latter is mixed with 2x mass of sulfur, loaded into a Pyrex tube, sealed and heated at 500 C for 4hrs to obtain Fe52@C nanocomposite. The product is washed with CS2 to remove any residual elemental sulfur. To synthesize y-Fe203@C and a-Fe203@C
composites, Fe304@C powder is heated in air at 350 C for 5hrs and 390 C for lhr, respectively, to obtain the products. To synthesize V205@C, VC13 is used as the starting material to synthesize V(C10f119C00)3. After polymerizing with acrylonitrile, the material is pyrolysed at 500 C in argon for 2hrs and then heated in air at 390 C for lhourto obtain V205@C. To synthesize FeSn2@C nanocomposite, tin undecylenate (Sn(C10f119C00)2) was synthesized in a similar fashion as iron undecylenate, except with SnC12 as the starting material. 2.2g Fe(C10f119C00)3 and 1.8g Sn(C10f119C00)2 were mixed first, 2m1 AN and 2m1 DVB were added, and then the rest of the procedure was carried out as above.
[0143] The crystal structures of the particles were characterized using Scintag Theta-theta PAD-X X-Ray Diffractometer (Cu Ka, 2,= 1.5406 A) and their morphologies were studied using ELI Tecnai G2 T12 Spirit Transmission Electron Microscope (120kV).
Thermogravimetric analysis was performed using TA Instruments Q5000 IR
Thermogravimetric Analyzer.
[0144] Cell assembly and testing. Electrochemical characterization of the composites as anode materials in rechargeable lithium-ion batteries was performed at room temperature in 2032 coin-type cells. The working electrode consisted of 80 wt% of the active material, 10 wt% of carbon black (Super-P Li from TIMCAL) as a conductivity aid, and 10 wt%
of polymer binder (PVDF, polyvinylidene fluoride, Aldrich). Copper foil was used as the current collector for nanocomposites targeted for application as the LIB anode and aluminum for those targeted as cathodes. Lithium foil was used as the counter and reference electrode for evaluating both that anode and cathode materials. A 1 M solution of LiPF6 in a 50:50 w/w
- 28 -2500 polypropylene membranes are used as the separator. Assembly of cell was performed in a glove box with moisture and oxygen concentrations below 1 ppm. The room-temperature electrode capacities were measured using Neware CT-3008 battery testers.
Cyclic voltammetry was performed with a CHI600D potentiostat.
[0145] Figure 30 illustrates the chemistry of a miniemulsion polymerization methodology that could be used to create organic-inorganic hybrid copolymers with high inorganic loadings. Using an organic monomer (e.g. acrylonitrile, or AN) and the metal salt of an unsaturated carboxylic acid (e.g. iron (III) undecylenate) and divinylbenzene as crosslinker the method yields well-defined iron oxide nanoparticles uniformly embedded in a polyacrylonitrile host (Figure 31A). FTIR spectra of iron (III) undecylenate and the AN-iron copolymer composite are compared in Figure 39. Significant decrease in the intensity of the C=C stretch peak at around 1640 cm-1 (normalized with respect to C-H stretch at around 2910 -1 i cm ) s observed, showing that as expected many of the double bonds in iron (III) undecylenate have been eliminated during polymerization.
[0146] Upon thermal treatment, the as prepared polyacrylonitrile (PAN) ¨
nanoparticle hybrids are transformed into carbon-Fe304 nanocomposites characterized by the uniform distribution of Fe304 in a partially graphitic carbon host was demonstrated. When evaluated as the anode in a lithium ion battery, the material showed significantly improved cycling stability and capacity retention relative to anodes based on pristine Fe304 nanoparticles. The performance enhancement brought about by the in situ synthesis approach was argued to largely originate from the uniform separation of the embedded nanoparticles achieved in the composites, which simultaneously minimizes aggregation of the active nanostructures, facilitates electron transport, and maximizes the degree to which the carbon framework is able to absorb and isolate mechanical stresses produced by structural changes.
Figure 31B shows the TEM image of the nanocomposite after 100 charge-discharge cycles. It indicates that with the mechanical support provided by the carbon matrix, the pulverization of the active material nanoparticles is mitigated, which is the source of the observed improvement in cyclability.
[0147] A goal of the present work is to illustrate the versatility of the synthesis method and to evaluate the generality of the hybrids produced. Figure 32 shows an abbreviated list that identifies the variety of hybrid materials relevant for application in lithium battery electrodes that can be synthesized using the approach. Because of the large number of Fe-based compounds and alloys that are of interest for LIB
applications,
Cyclic voltammetry was performed with a CHI600D potentiostat.
[0145] Figure 30 illustrates the chemistry of a miniemulsion polymerization methodology that could be used to create organic-inorganic hybrid copolymers with high inorganic loadings. Using an organic monomer (e.g. acrylonitrile, or AN) and the metal salt of an unsaturated carboxylic acid (e.g. iron (III) undecylenate) and divinylbenzene as crosslinker the method yields well-defined iron oxide nanoparticles uniformly embedded in a polyacrylonitrile host (Figure 31A). FTIR spectra of iron (III) undecylenate and the AN-iron copolymer composite are compared in Figure 39. Significant decrease in the intensity of the C=C stretch peak at around 1640 cm-1 (normalized with respect to C-H stretch at around 2910 -1 i cm ) s observed, showing that as expected many of the double bonds in iron (III) undecylenate have been eliminated during polymerization.
[0146] Upon thermal treatment, the as prepared polyacrylonitrile (PAN) ¨
nanoparticle hybrids are transformed into carbon-Fe304 nanocomposites characterized by the uniform distribution of Fe304 in a partially graphitic carbon host was demonstrated. When evaluated as the anode in a lithium ion battery, the material showed significantly improved cycling stability and capacity retention relative to anodes based on pristine Fe304 nanoparticles. The performance enhancement brought about by the in situ synthesis approach was argued to largely originate from the uniform separation of the embedded nanoparticles achieved in the composites, which simultaneously minimizes aggregation of the active nanostructures, facilitates electron transport, and maximizes the degree to which the carbon framework is able to absorb and isolate mechanical stresses produced by structural changes.
Figure 31B shows the TEM image of the nanocomposite after 100 charge-discharge cycles. It indicates that with the mechanical support provided by the carbon matrix, the pulverization of the active material nanoparticles is mitigated, which is the source of the observed improvement in cyclability.
[0147] A goal of the present work is to illustrate the versatility of the synthesis method and to evaluate the generality of the hybrids produced. Figure 32 shows an abbreviated list that identifies the variety of hybrid materials relevant for application in lithium battery electrodes that can be synthesized using the approach. Because of the large number of Fe-based compounds and alloys that are of interest for LIB
applications,
- 29 -compounds; the enhancements were subsequently evaluated in their properties by using the composites as anodes or cathodes for LIBs. Results on other examples (e.g.
materials based on vanadium and titanium) will also be discussed.
[0148] As illustrated in Figure 32, carbon-Fe304 nanocomposites (Fe304@C) synthesized using the procedures outlined earlier can be reduced to Fe@C
composites either by heating the material in an H2 environment or simply by heating the composite in an inert gas to a temperature somewhat higher than the carbonization temperature (whereby carbon serves as the reducing agent). The XRD pattern of the material obtained after heating Fe304@C to 650-700 C under H2 is shown in Figure 33A, which is unambiguously assigned to the a-Fe (JCPDS card #06-0696). Figure 33B is a transmission electron micrograph of the material showing that the materials are comprised of well-dispersed ca. 30 nm Fe nanoparticles, which is consistent with the average crystallite size of 29nm deduced from XRD.
[0149] Because the carbon matrix is porous, it allows the infusion of other chemical agents, which can react with the embedded Fe nanoparticles. FeS2 is a promising cathode material for lithium batteries because of its high reversible capacity (625 mAh/g), low cost and low toxicity. It is well-known in primary lithium battery applications and high temperature thermal batteries, but its use in room-temperature rechargeable cells has been hindered by the material's limited cyclability. A vapor infusion procedure was used to react the Fe@C composites with sulfur at 500 C. Figures 33A and C are the conesponding XRD
and TEM patterns for this material. The XRD pattern is unambiguously assigned to FeS2 (JCPDS card # 42-1340) and reveals that reaction with sulfur has nearly doubled the crystallite size to 54nm; again consistent with results from TEM, which show uniformly distributed ca. 55nm FeS2 particles in the carbon host. Particle size histograms obtained from TEM images for Fe@C and FeS2@C composites are shown in Figures 33(D) and (E), with average sizes of 29.7 3.8nm and 53.8 9.9nm, respectively. Through oxidative TGA (Figure 40) the weight fraction of FeS2 in the product is found to be 75%.
[0150] Figure 34 report results from cyclic voltammetry and galvanostatic cycling measurements performed using the as prepared FeS2@C composites. In the cathodic scan of the first cycle, FeS2 follows a two-step lithiation: FeS2+ 2Li+ + 2e Li2FeS2 (-2V) and Li2FeS2 + 2Li+ + 2e Fe + 2Li2S (-1.4V). In the anodic scans, the material is converted to Li2FeS2 at around 1.8V and then to Li2FeS2 (0<x<0.8) at around 2.5V. At room temperature if the material is driven to high potentials (above 2.45V), instead of regenerating the FeS2
materials based on vanadium and titanium) will also be discussed.
[0148] As illustrated in Figure 32, carbon-Fe304 nanocomposites (Fe304@C) synthesized using the procedures outlined earlier can be reduced to Fe@C
composites either by heating the material in an H2 environment or simply by heating the composite in an inert gas to a temperature somewhat higher than the carbonization temperature (whereby carbon serves as the reducing agent). The XRD pattern of the material obtained after heating Fe304@C to 650-700 C under H2 is shown in Figure 33A, which is unambiguously assigned to the a-Fe (JCPDS card #06-0696). Figure 33B is a transmission electron micrograph of the material showing that the materials are comprised of well-dispersed ca. 30 nm Fe nanoparticles, which is consistent with the average crystallite size of 29nm deduced from XRD.
[0149] Because the carbon matrix is porous, it allows the infusion of other chemical agents, which can react with the embedded Fe nanoparticles. FeS2 is a promising cathode material for lithium batteries because of its high reversible capacity (625 mAh/g), low cost and low toxicity. It is well-known in primary lithium battery applications and high temperature thermal batteries, but its use in room-temperature rechargeable cells has been hindered by the material's limited cyclability. A vapor infusion procedure was used to react the Fe@C composites with sulfur at 500 C. Figures 33A and C are the conesponding XRD
and TEM patterns for this material. The XRD pattern is unambiguously assigned to FeS2 (JCPDS card # 42-1340) and reveals that reaction with sulfur has nearly doubled the crystallite size to 54nm; again consistent with results from TEM, which show uniformly distributed ca. 55nm FeS2 particles in the carbon host. Particle size histograms obtained from TEM images for Fe@C and FeS2@C composites are shown in Figures 33(D) and (E), with average sizes of 29.7 3.8nm and 53.8 9.9nm, respectively. Through oxidative TGA (Figure 40) the weight fraction of FeS2 in the product is found to be 75%.
[0150] Figure 34 report results from cyclic voltammetry and galvanostatic cycling measurements performed using the as prepared FeS2@C composites. In the cathodic scan of the first cycle, FeS2 follows a two-step lithiation: FeS2+ 2Li+ + 2e Li2FeS2 (-2V) and Li2FeS2 + 2Li+ + 2e Fe + 2Li2S (-1.4V). In the anodic scans, the material is converted to Li2FeS2 at around 1.8V and then to Li2FeS2 (0<x<0.8) at around 2.5V. At room temperature if the material is driven to high potentials (above 2.45V), instead of regenerating the FeS2
- 30 -transformation from Li2õFeS2(hexagonal) to FeSx (hexagonal). Subsequent cycling occurs between Li2õFeS2 and Fe/Li25. Voltage-capacity profiles at different charging rates are shown in Figure 41. Plateaus at ¨2V and 1.4-1.5V in the discharge curve correspond to lithiation peaks in the anodic scan. The gravimetric capacity is calculated with respect to active material mass (the same for the materials to follow in this work). The cyclability is compared with commercially available pristine Fe52, showing the enhancement of cycling performance brought about by forming nanocomposites with carbon.
[0151] When more than one metal precursor is used, the approach yielded nanocomposites with alloy nanoparticles embedded in the carbon matrix. An example of this is the iron-tin alloy, which is being actively investigated as an anode material in LIBs. Alloys of tin with another metal (e.g. Sb, Co, Fe, Ni) are able to provide some alleviation effect for the pulverization of tin through the mechanical protection offered by the other metal which gets extruded during lithiation. The incorporation of such alloy nanoparticles in a carbon matrix provides a means of additional mechanical support so that the cycling stability of the material may be further enhanced.
[0152] FeSn2@C nanocomposites can be synthesized using a combination of iron and tin precursors, as confirmed by XRD (Figure 35A). EDX indicates the presence of iron and tin in the composite (Figures 35C and 35D) and yields an atomic ratio of Fe/Sn=0.59. The weight fraction of FeSn2in the composite is determined using oxidative TGA to be 68%
(Figure 40). The TEM images are shown in Figure 35B. There appears to be a broader distribution of nanoparticle size compared to other materials (e.g. metal oxides, sulfides) synthesized using the same approach. The reason may be that tin has a relatively low melting point and liquid tin likely formed droplets with broad size distribution before reacting with iron. Cyclic voltammograms of the material are shown in Figure 36A. The electrochemical reaction of FeSn2 in LIB can be expressed as follows: FeSn2+ 8.8Li+ + 8.8e 2Li445n + Fe and Li445n Sn + 4.4 Li + + 4.4e. The reversible capacity of the material results from the repeated alloying and dealloying of lithium with tin. Multiple lithiation peaks occur in the CV
indicating the multi-step reaction associated with Li-Sn alloying. Some of the important intermediate phases include Li75n3 (formed at ¨0.45V vs. Li/Lit) and Li75n2(-0.28V).
Overlapping with the SEI formation peak may have caused some broadening of these lithiation peaks. The cycling performance of the composite at different rates is compared with
[0151] When more than one metal precursor is used, the approach yielded nanocomposites with alloy nanoparticles embedded in the carbon matrix. An example of this is the iron-tin alloy, which is being actively investigated as an anode material in LIBs. Alloys of tin with another metal (e.g. Sb, Co, Fe, Ni) are able to provide some alleviation effect for the pulverization of tin through the mechanical protection offered by the other metal which gets extruded during lithiation. The incorporation of such alloy nanoparticles in a carbon matrix provides a means of additional mechanical support so that the cycling stability of the material may be further enhanced.
[0152] FeSn2@C nanocomposites can be synthesized using a combination of iron and tin precursors, as confirmed by XRD (Figure 35A). EDX indicates the presence of iron and tin in the composite (Figures 35C and 35D) and yields an atomic ratio of Fe/Sn=0.59. The weight fraction of FeSn2in the composite is determined using oxidative TGA to be 68%
(Figure 40). The TEM images are shown in Figure 35B. There appears to be a broader distribution of nanoparticle size compared to other materials (e.g. metal oxides, sulfides) synthesized using the same approach. The reason may be that tin has a relatively low melting point and liquid tin likely formed droplets with broad size distribution before reacting with iron. Cyclic voltammograms of the material are shown in Figure 36A. The electrochemical reaction of FeSn2 in LIB can be expressed as follows: FeSn2+ 8.8Li+ + 8.8e 2Li445n + Fe and Li445n Sn + 4.4 Li + + 4.4e. The reversible capacity of the material results from the repeated alloying and dealloying of lithium with tin. Multiple lithiation peaks occur in the CV
indicating the multi-step reaction associated with Li-Sn alloying. Some of the important intermediate phases include Li75n3 (formed at ¨0.45V vs. Li/Lit) and Li75n2(-0.28V).
Overlapping with the SEI formation peak may have caused some broadening of these lithiation peaks. The cycling performance of the composite at different rates is compared with
-31 -enhancement over the bare material is clearly seen.
[0153] Ex situ treatment may also be performed on metal oxides themselves to yield the oxides with different valences of the metal. This brings about a method to overcome the limitations on the types of metal oxides that can be synthesized using the current approach.
There are two main reasons for this limitation. One is that in general metal salts with higher valences has a higher tendency to hydrolyze and the corresponding carboxylic acid salt may be more difficult to synthesize. For example, only Mn(C10H19C00)2 can be synthesized using the current approach and not Mn(C10fl19C00)3. The other is that with a given precursor, usually only one type of metal oxide can be obtained from the direct pyrolysis of the precursor. For example, the pyrolysis of the Fe(C10H19C00)3precursor only yields magnetite and does not directly give maghemite or hematite. With ex situ oxidation, the composites involving lower-valence metal oxides may be transformed into composites containing metal oxides with higher valences, which cannot be directly made. For example, Fe304 (magnetite) may be oxidized to maghemite or hematite and MnO may be oxidized to form Mn304. The XRD patterns of a-Fe@C (JCPDS card #06-0696), Fe304@C (#19-0629), a-Fe203@C
(#33-0664) and y-Fe203@C (#25-1402) are shown in Figure 37A and TEM image for y-Fe203@C
in 6B.
[0154] Another example is vanadium. V(V) salt is not stable in water and V205 cannot be directly synthesized using this approach. However, V(III) salt may be used to synthesize V(C10H19C00)3 precursor which can be pyrolysed to form V02@C which is then oxidized in air to give V205@C composite. The XRD patterns and TEM images of V205@C
(JCPDS card #41-1426) and Ti02@C (anatase, JCPDS card #21-1272) are shown in Figures 37C-F.
[0155] The electrochemical performance of y-Fe203@C was tested. a-Fe203 has been extensively investigated as LIB electrode materials undergoing either intercalation mechanism at low levels of lithiation or conversion reaction at high levels of lithiation and there have also been some reports on y-Fe203. Cyclic voltammograms of they-Fe203@C
composite synthesized using the current method are shown in Figure 38A. Fe203 nanoparticles follow the reversible conversion reaction Fe203+ 6Li+ +6e 2Fe +3Li20 when fully lithiated. The large peak in the first cathodic scan at ¨0.5V vs.
Li/Lit is usually attributed to SEI formation and in the subsequent cycles lithiation of Fe203 takes place at ¨0.8V corresponding to the reduction of Fe3+ to Fe . The broad peak centered at ¨1.7V in the
[0153] Ex situ treatment may also be performed on metal oxides themselves to yield the oxides with different valences of the metal. This brings about a method to overcome the limitations on the types of metal oxides that can be synthesized using the current approach.
There are two main reasons for this limitation. One is that in general metal salts with higher valences has a higher tendency to hydrolyze and the corresponding carboxylic acid salt may be more difficult to synthesize. For example, only Mn(C10H19C00)2 can be synthesized using the current approach and not Mn(C10fl19C00)3. The other is that with a given precursor, usually only one type of metal oxide can be obtained from the direct pyrolysis of the precursor. For example, the pyrolysis of the Fe(C10H19C00)3precursor only yields magnetite and does not directly give maghemite or hematite. With ex situ oxidation, the composites involving lower-valence metal oxides may be transformed into composites containing metal oxides with higher valences, which cannot be directly made. For example, Fe304 (magnetite) may be oxidized to maghemite or hematite and MnO may be oxidized to form Mn304. The XRD patterns of a-Fe@C (JCPDS card #06-0696), Fe304@C (#19-0629), a-Fe203@C
(#33-0664) and y-Fe203@C (#25-1402) are shown in Figure 37A and TEM image for y-Fe203@C
in 6B.
[0154] Another example is vanadium. V(V) salt is not stable in water and V205 cannot be directly synthesized using this approach. However, V(III) salt may be used to synthesize V(C10H19C00)3 precursor which can be pyrolysed to form V02@C which is then oxidized in air to give V205@C composite. The XRD patterns and TEM images of V205@C
(JCPDS card #41-1426) and Ti02@C (anatase, JCPDS card #21-1272) are shown in Figures 37C-F.
[0155] The electrochemical performance of y-Fe203@C was tested. a-Fe203 has been extensively investigated as LIB electrode materials undergoing either intercalation mechanism at low levels of lithiation or conversion reaction at high levels of lithiation and there have also been some reports on y-Fe203. Cyclic voltammograms of they-Fe203@C
composite synthesized using the current method are shown in Figure 38A. Fe203 nanoparticles follow the reversible conversion reaction Fe203+ 6Li+ +6e 2Fe +3Li20 when fully lithiated. The large peak in the first cathodic scan at ¨0.5V vs.
Li/Lit is usually attributed to SEI formation and in the subsequent cycles lithiation of Fe203 takes place at ¨0.8V corresponding to the reduction of Fe3+ to Fe . The broad peak centered at ¨1.7V in the
-32-cyclic voltammograms indicates stable cycling performance, which is shown in Figure 38B at 1C, 0.5C and 2C charging rates.
[0156] Since the active material is incorporated in an amorphous carbon matrix, which does not make a significant contribution to the lithiation capacity, it is useful to determine the effect of the carbon. Using as an example the Fe304-carbon nanocomposite containing 66% by weight Fe304 (924mAh/g) and the balance carbon (40mAh/g), the gravimetric theoretical capacity of the composite is 620 mAh/g. From mercury porosimetry, the pore volume of carbon is found to be 0.5516 ml/g and assuming the bulk densities of magnetite and amorphous carbon to be 5.2 and 2.1 g/cm3, respectively, the volumetric theoretical capacities of magnetite and the composite are 4.81 and 1.30 Ah/cm3. Therefore the employment of the porous carbon matrix comes at the cost of a reduced volumetric capacity, which can be limited in an actual battery design by engineering the porosity and weight fraction of the carbon matrix to achieve desired gravimetric and volumetric capacity goals while preserving the improving cyclability imparted by the porous carbon support.
[0157] In conclusion, a platform has been developed whereby through the copolymerization of organic and inorganic starting materials and formation of a hybrid followed by calcination, embedded nanostructures consisting of uniformly sized nanoparticles incorporated in a porous carbon matrix may be synthesized in situ. Either by mere in situ reaction, or combined with ex situ engineering of the embedded material, a wide variety of embedded nanostructures may be synthesized which show enhanced lithium storage performance over the bare material. The method obviates the relatively stringent experimental control required in many other methods of creating carbon composites and provides a convenient way to prevent the aggregation of particles. Therefore the process lends itself to cheap and facile scale-up. Besides the materials, which have been demonstrated, additional categories of materials can be made using the current approach (e.g. silicon and phosphates), which is part of the ongoing work.
[0158] While the invention has been particularly shown and described with reference to specific embodiments (some of which are preferred embodiments), it should be understood by those having skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the present invention as disclosed herein.
[0156] Since the active material is incorporated in an amorphous carbon matrix, which does not make a significant contribution to the lithiation capacity, it is useful to determine the effect of the carbon. Using as an example the Fe304-carbon nanocomposite containing 66% by weight Fe304 (924mAh/g) and the balance carbon (40mAh/g), the gravimetric theoretical capacity of the composite is 620 mAh/g. From mercury porosimetry, the pore volume of carbon is found to be 0.5516 ml/g and assuming the bulk densities of magnetite and amorphous carbon to be 5.2 and 2.1 g/cm3, respectively, the volumetric theoretical capacities of magnetite and the composite are 4.81 and 1.30 Ah/cm3. Therefore the employment of the porous carbon matrix comes at the cost of a reduced volumetric capacity, which can be limited in an actual battery design by engineering the porosity and weight fraction of the carbon matrix to achieve desired gravimetric and volumetric capacity goals while preserving the improving cyclability imparted by the porous carbon support.
[0157] In conclusion, a platform has been developed whereby through the copolymerization of organic and inorganic starting materials and formation of a hybrid followed by calcination, embedded nanostructures consisting of uniformly sized nanoparticles incorporated in a porous carbon matrix may be synthesized in situ. Either by mere in situ reaction, or combined with ex situ engineering of the embedded material, a wide variety of embedded nanostructures may be synthesized which show enhanced lithium storage performance over the bare material. The method obviates the relatively stringent experimental control required in many other methods of creating carbon composites and provides a convenient way to prevent the aggregation of particles. Therefore the process lends itself to cheap and facile scale-up. Besides the materials, which have been demonstrated, additional categories of materials can be made using the current approach (e.g. silicon and phosphates), which is part of the ongoing work.
[0158] While the invention has been particularly shown and described with reference to specific embodiments (some of which are preferred embodiments), it should be understood by those having skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the present invention as disclosed herein.
-33 -
Claims (18)
1) A method for forming a material comprising the steps of:
contacting one or more monomers, one or more metal precursor compounds, optionally, an initiator, and optionally, one or more solvents, to form a reaction mixture, heating the reaction mixture such that a hybrid material comprising a plurality of metal precursor compounds chemically bonded to the polymer matrix is formed and, optionally, isolating the hybrid material.
contacting one or more monomers, one or more metal precursor compounds, optionally, an initiator, and optionally, one or more solvents, to form a reaction mixture, heating the reaction mixture such that a hybrid material comprising a plurality of metal precursor compounds chemically bonded to the polymer matrix is formed and, optionally, isolating the hybrid material.
2) The method of claim 1, further comprising the step of pyrolysing the hybrid material, such that a nanocomposite material comprising a plurality of nanoparticles embedded in a carbon matrix is formed, the nanoparticles being formed from the metal component of the one or more metal precursor compounds.
3) The method of claim 1, wherein the reaction mixture comprises:
a first monomer, optionally, a second monomer, wherein the second monomer is a cross-linking monomer, a metal precursor compound, an initiator, an anionic surfactant, water, and one or more organic solvents, such that a reaction mixture that is an aqueous emulsion is formed.
a first monomer, optionally, a second monomer, wherein the second monomer is a cross-linking monomer, a metal precursor compound, an initiator, an anionic surfactant, water, and one or more organic solvents, such that a reaction mixture that is an aqueous emulsion is formed.
4) The method of claim 1, wherein the reaction mixture comprises:
a first monomer, optionally, a second monomer, a metal precursor compound, and
a first monomer, optionally, a second monomer, a metal precursor compound, and
5) The method of claim 1, wherein the reaction mixture comprises a plurality of metal precursors, wherein the metal precursors have a different metal.
6) The method of claim 1, wherein the one or more monomers are selected from the group consisting of acrylonitrile, divinyl benzene, resorcinol, formaldehyde, vinylpyrrolidone, vinyl alcohol, acrylic acid, phenol, 1,4-butadiene, isoprene, vinylsilane, sulfur, and combinations thereof.
7) The method of claim 1, wherein the one or more metal precursor compounds are selected from the group consisting of metal carboxylates, metal coordination compounds, and combinations thereof.
8) The method of claim 2, further comprising reducing the metal oxide nanoparticles of the nanocomposite material comprising a plurality of metal oxide nanoparticles embedded in a carbon matrix by contacting the nanocomposite material with a reductant or heating the nanocomposite material under inert conditions, such that a nanocomposite material comprising a plurality of metal nanoparticles embedded in a carbon matrix is formed.
9) The method of claim 2, further comprising contacting the nanocomposite material comprising a plurality of metal oxide nanoparticles embedded in a carbon matrix with a sulfur compound, halide compound, or phosphate compound, such that a nanocomposite material comprising a plurality of metal sulfide, metal halide, or metal phosphate nanoparticles embedded in a carbon matrix is formed.
10) The method of claim 2, further comprising reducing the metal sulfide nanoparticles of the nanocomposite material comprising a plurality of metal sulfide nanoparticles embedded nanocomposite material under inert conditions, such that a nanocomposite material comprising a plurality of metal nanoparticles embedded in a carbon matrix is formed.
11) The method of claim 2, further comprising contacting the nanocomposite material comprising a plurality of metal sulfide nanoparticles embedded in a carbon matrix with an oxygen compound, halide compound, or phosphate compound, such that a nanocomposite material comprising a plurality of metal oxide, metal halide, or metal phosphate nanoparticles embedded in a carbon matrix is formed.
12) A hybrid material comprising a plurality of metal precursor compounds embedded in a polymer, wherein the metal precursor compounds are chemically bonded to the polymer and uniformly distributed in the polymer.
13) The hybrid material of claim 12, wherein the metal precursor compounds are selected from the group consisting of metal carboxylates, metal coordination compounds, and combinations thereof.
14) The hybrid material of claim 12, wherein the polymer is poly(acrylonitrile), polyvinylpyrroilidone, polysaccharide, acrylonitrile-divinylbenzene copolymer, phenol resin, or resorcinol-formaldehyde copolymer.
15) A nanocomposite material comprising a plurality of nanoparticles embedded in a carbon matrix, wherein the nanoparticles are present at 40 % by weight to 90 % by weight, are from 5 nm to 500 nm in diameter, and no phase separation between the carbon matrix and nanoparticles is observed.
-36-Fe@C, Mn@C, FeSn2@C, Fe2O3@C (e.g., .alpha.-Fe2O3@C, 7- Fe2O3@C), Fe3O4@C, CuO@C, Cu2O@C, MnO@C, Mn3O4@C, Mn2O3@C, VO2@C, V2O5@C, TiO2@C, MoS2@C, FeS2@C, CuF2@C, LiFePO4@C and LiMn x Fe1-x PO4@C, ZnO@C, ZrO2@C, TiO2@C, Co@C, CoS@C, Mn0.75Fe0.250@C, LiMn0.75Fe0.25PO4@C, Sn@C, Co3O4@C, or Cu@C.
17) A device comprising the nanocomposite material of claim 11.
18) The device of claim 17, wherein the device is a battery or an on-chip inductor.
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201161503085P | 2011-06-30 | 2011-06-30 | |
US61/503,085 | 2011-06-30 | ||
US201161578464P | 2011-12-21 | 2011-12-21 | |
US61/578,464 | 2011-12-21 | ||
PCT/US2012/045188 WO2013003836A2 (en) | 2011-06-30 | 2012-07-02 | Hybrid materials and nanocomposite materials, methods of making same, and uses thereof |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2840747A1 true CA2840747A1 (en) | 2013-01-03 |
Family
ID=47424829
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA2840747A Abandoned CA2840747A1 (en) | 2011-06-30 | 2012-07-02 | Hybrid materials and nanocomposite materials, methods of making same, and uses thereof |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP2726403A4 (en) |
JP (1) | JP2014523468A (en) |
KR (1) | KR20140050016A (en) |
CN (1) | CN103764546B (en) |
AU (1) | AU2012275046A1 (en) |
CA (1) | CA2840747A1 (en) |
WO (1) | WO2013003836A2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103578796A (en) * | 2013-11-15 | 2014-02-12 | 复旦大学 | Preparation method of super-capacitor electrode without adhesives |
CN113540422A (en) * | 2021-07-14 | 2021-10-22 | 路华置富电子(深圳)有限公司 | Silicon-carbon shell nano composite material, preparation method and lithium ion battery electrode |
Families Citing this family (29)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6129535B2 (en) * | 2012-12-14 | 2017-05-17 | 昭和電工株式会社 | Negative electrode material for lithium battery, method for producing the same, electrode, and battery |
CN103762347B (en) * | 2014-01-24 | 2017-01-04 | 上海理工大学 | A kind of electrode material and preparation method thereof |
CN103819601B (en) * | 2014-02-10 | 2016-01-20 | 绍兴文理学院 | The multi-component reaction preparation method of functionalized nano porous polymer material |
US20170222217A1 (en) * | 2014-05-05 | 2017-08-03 | Nivo Systems, Inc. | Carbon-enriched open framework composites, methods for producing and using such composites |
KR101580143B1 (en) * | 2014-06-03 | 2015-12-28 | 연세대학교 산학협력단 | magnetic particle embedded porous carbon composites and their synthetic method |
CN106575753A (en) * | 2014-06-13 | 2017-04-19 | 东北大学 | Layered metal oxide cathode material for lithium ion batteries |
JP6344143B2 (en) * | 2014-08-27 | 2018-06-20 | 日本ゼオン株式会社 | Method for producing composite particle for electrochemical element electrode, method for producing electrochemical element electrode, and method for producing electrochemical element |
WO2016098608A1 (en) * | 2014-12-16 | 2016-06-23 | 大塚化学株式会社 | Method for producing composite body of lithium titanate particles and carbonaceous material, and composite body of lithium titanate particles and carbonaceous material |
JP6706804B2 (en) * | 2015-02-27 | 2020-06-10 | 住友ベークライト株式会社 | Metal hybrid resin and manufacturing method thereof |
CN104752073B (en) * | 2015-04-15 | 2017-04-05 | 北京化工大学 | A kind of preparation method of manganese iron axinite/carbon composite |
CN105047914B (en) * | 2015-05-28 | 2017-11-17 | 东南大学 | A kind of lithium ion battery negative material molybdenum disulfide/carbon and preparation method thereof |
KR101715499B1 (en) * | 2015-08-25 | 2017-03-13 | 성균관대학교산학협력단 | Method of manufacturing a fine particle and organic-inorganic hybrid particle |
CN105273778B (en) * | 2015-10-08 | 2017-09-19 | 丘濠玮 | A kind of preparation method of fuel activating agent |
CN105273779B (en) * | 2015-10-08 | 2017-09-19 | 丘濠玮 | A kind of fuel activating agent and preparation method thereof |
CN105618087B (en) * | 2016-01-03 | 2018-10-16 | 复旦大学 | A kind of two chalcogen compound nanoscale twins compound of transition metal and preparation method thereof |
CN105655562B (en) * | 2016-03-01 | 2018-01-16 | 华东师范大学 | Carbon skeleton nanobelt carries MoS2Nanometer bead nano composite material and preparation method thereof |
CN106268873A (en) * | 2016-08-03 | 2017-01-04 | 江南大学 | A kind of composite magnetic catalyst for Bisphenol F |
CN107085024B (en) * | 2017-05-16 | 2019-04-02 | 山东理工大学 | A kind of preparation method and application for the immunosensor detecting hepatitis b virus marker |
CN107611009B (en) * | 2017-08-30 | 2020-10-13 | 尚妙根 | Preparation method of zinc oxide composite semiconductor material |
US11813676B2 (en) * | 2019-02-13 | 2023-11-14 | Instituto Tecnológico y de Estudios Superiores de Monterrey | Migration of nano metals in semisolid and solid matrix under the influence of selectively triggered heterogeneous nucleation and growth |
CN109841821B (en) * | 2019-03-18 | 2021-06-18 | 贵州梅岭电源有限公司 | High-potential high-power thermal battery anode material and preparation method thereof |
CN109888262B (en) * | 2019-04-14 | 2022-03-01 | 烟台大学 | Double-layer coated graphite composite material and preparation method and application thereof |
CN111554905B (en) * | 2020-05-14 | 2020-12-29 | 云南民族大学 | Preparation method, product and application of zinc oxide-based carbon composite nano material |
US12002958B2 (en) | 2020-05-28 | 2024-06-04 | Resonac Corporation | Composite particles, negative electrode active material, and lithium-ion secondary battery |
KR20230015992A (en) * | 2020-05-28 | 2023-01-31 | 쇼와 덴코 가부시키가이샤 | Negative electrode material for lithium ion secondary battery and its use |
CN111498831A (en) * | 2020-06-02 | 2020-08-07 | 上海交通大学 | In-situ space-limited growth of two-dimensional MoS in carbon nanocapsules2Nano-sheet |
CN111604075B (en) * | 2020-06-28 | 2023-07-25 | 江苏新瀚新材料股份有限公司 | Carbon-supported iron carbide catalyst for Friedel-crafts acylation reaction and preparation method thereof |
KR102563523B1 (en) * | 2020-12-29 | 2023-08-10 | 한국과학기술연구원 | Method for manufacturing composite electrode for secondary battery, and composite electrode for secondary battery manufactured thereby |
CN114538424B (en) * | 2022-03-22 | 2023-07-14 | 中国科学技术大学 | Preparation method of ordered mesoporous carbon modified graphene material |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1137925C (en) * | 2001-04-18 | 2004-02-11 | 中国科学院理化技术研究所 | Method for preparing metal sulfide nano-particle/polymer composite material |
CN1314750C (en) * | 2005-07-20 | 2007-05-09 | 中国科学院上海硅酸盐研究所 | Microwave liquid phase preparation method of polyacrylamide base metal nanometer composite material |
US7385003B1 (en) * | 2005-10-03 | 2008-06-10 | Sandia Corporation | In-situ formation of nanoparticles within a silicon-based matrix |
US20090272949A1 (en) * | 2008-03-20 | 2009-11-05 | The Blue Sky Group | Method for Producing Metal Oxide Nanoparticles Encapsulated with Conducting Polymers |
KR101322165B1 (en) * | 2009-03-03 | 2013-10-28 | 칭화대학교 | Process for preparing alloy composite negative electrode material for lithium ion batteries |
-
2012
- 2012-07-02 CA CA2840747A patent/CA2840747A1/en not_active Abandoned
- 2012-07-02 WO PCT/US2012/045188 patent/WO2013003836A2/en active Application Filing
- 2012-07-02 JP JP2014519216A patent/JP2014523468A/en active Pending
- 2012-07-02 CN CN201280042437.0A patent/CN103764546B/en not_active Expired - Fee Related
- 2012-07-02 EP EP12804017.7A patent/EP2726403A4/en not_active Withdrawn
- 2012-07-02 AU AU2012275046A patent/AU2012275046A1/en not_active Abandoned
- 2012-07-02 KR KR1020147002192A patent/KR20140050016A/en not_active Application Discontinuation
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103578796A (en) * | 2013-11-15 | 2014-02-12 | 复旦大学 | Preparation method of super-capacitor electrode without adhesives |
CN113540422A (en) * | 2021-07-14 | 2021-10-22 | 路华置富电子(深圳)有限公司 | Silicon-carbon shell nano composite material, preparation method and lithium ion battery electrode |
Also Published As
Publication number | Publication date |
---|---|
WO2013003836A2 (en) | 2013-01-03 |
EP2726403A4 (en) | 2015-04-08 |
WO2013003836A9 (en) | 2014-01-30 |
CN103764546A (en) | 2014-04-30 |
AU2012275046A1 (en) | 2014-01-23 |
AU2012275046A9 (en) | 2014-02-20 |
KR20140050016A (en) | 2014-04-28 |
WO2013003836A3 (en) | 2013-04-25 |
EP2726403A2 (en) | 2014-05-07 |
CN103764546B (en) | 2019-08-20 |
JP2014523468A (en) | 2014-09-11 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US10950849B2 (en) | Hybrid materials and nanocomposite materials, methods of making same, and uses thereof | |
CA2840747A1 (en) | Hybrid materials and nanocomposite materials, methods of making same, and uses thereof | |
Yang et al. | An in situ method of creating metal oxide–carbon composites and their application as anode materials for lithium-ion batteries | |
Rui et al. | Reduced graphene oxide supported highly porous V 2 O 5 spheres as a high-power cathode material for lithium ion batteries | |
JP5293936B2 (en) | Non-aqueous electrolyte secondary battery olivine-type composite oxide, method for producing the same, and secondary battery | |
JP5517032B2 (en) | Non-aqueous electrolyte secondary battery olivine-type composite oxide particle powder, method for producing the same, and secondary battery | |
Fathollahi et al. | Improved electrochemical properties of LiFePO4/graphene cathode nanocomposite prepared by one-step hydrothermal method | |
US9620783B2 (en) | Mesoporous metal oxide microsphere electrode compositions and their methods of making | |
KR101313350B1 (en) | open porous electrically conductive nanocomposite material | |
CA2778127C (en) | Hydrothermal process for the production of lifepo4 powder | |
US20090117020A1 (en) | Rapid microwave-solvothermal synthesis and surface modification of nanostructured phospho-olivine cathodes for lithium ion batteries | |
KR20110114483A (en) | Transition metal oxidenitrides | |
WO2013038516A1 (en) | Manganese iron ammonium phosphate, method for producing same, positive electrode active material for lithium secondary batteries using manganese iron ammonium phosphate, method for producing positive electrode active material for lithium secondary batteries using manganese iron ammonium phosphate, and lithium secondary battery using positive electrode active material for lithium secondary batteries using manganese iron ammonium phosphate | |
JP2013234088A (en) | Silicon composite and method of manufacturing the same, negative electrode active material, and nonaqueous secondary battery | |
WO2014171053A1 (en) | Binder for negative electrodes of secondary batteries, negative electrode of secondary battery, and lithium ion secondary battery | |
Zhang et al. | Carbon-encapsulated LiMn2O4 spheres prepared using a polymer microgel reactor for high-power lithium-ion batteries | |
KR20200114970A (en) | Positive electrode material for lithium-ion secondary batteries, positive electrode for lithium-ion secondary batteries, and lithium-ion secondary battery | |
Zhao et al. | Environmentally benign and scalable synthesis of LiFePO4 nanoplates with high capacity and excellent rate cycling performance for lithium ion batteries | |
WO2015131055A1 (en) | Composite material having domains of lithium oxometallates in a matrix | |
Behboudi-Khiavi et al. | Synthesis of mesoporous LixMnO2 as a cathode material of lithium ion battery via one-pot galvanostatic electrodeposition method | |
Mensing et al. | Advances in rechargeable magnesium batteries employing graphene-based materials | |
Ko et al. | The keys for effective distribution of intergranular voids of peapod-like MnO@ C core-shell for lithium ion batteries | |
KR101046432B1 (en) | Preparation of novel nanostructured titanium oxide nano-composite and its electrode application for charge storage devices | |
CN110690427B (en) | Preparation method of doped ternary material coated by polymeric aluminum-graphene | |
CN112635757B (en) | Positive electrode active material, preparation method thereof, electrochemical cell positive electrode material and electrochemical cell |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FZDE | Discontinued |
Effective date: 20180704 |