US20210057761A1 - Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same - Google Patents
Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same Download PDFInfo
- Publication number
- US20210057761A1 US20210057761A1 US17/088,732 US202017088732A US2021057761A1 US 20210057761 A1 US20210057761 A1 US 20210057761A1 US 202017088732 A US202017088732 A US 202017088732A US 2021057761 A1 US2021057761 A1 US 2021057761A1
- Authority
- US
- United States
- Prior art keywords
- fuel cell
- heat
- support
- carbon
- electrode
- 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.)
- Pending
Links
- 239000000446 fuel Substances 0.000 title claims abstract description 88
- 238000000034 method Methods 0.000 title claims description 39
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 127
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 106
- 239000000758 substrate Substances 0.000 claims abstract description 43
- 229920000642 polymer Polymers 0.000 claims description 35
- 238000010438 heat treatment Methods 0.000 claims description 29
- 238000006116 polymerization reaction Methods 0.000 claims description 23
- 238000000576 coating method Methods 0.000 claims description 13
- 239000000203 mixture Substances 0.000 claims description 13
- 239000011248 coating agent Substances 0.000 claims description 12
- 238000001237 Raman spectrum Methods 0.000 claims description 11
- 230000000087 stabilizing effect Effects 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 8
- 238000010000 carbonizing Methods 0.000 claims description 6
- 239000003505 polymerization initiator Substances 0.000 claims description 6
- 239000000178 monomer Substances 0.000 claims description 4
- 239000010410 layer Substances 0.000 description 64
- 239000003054 catalyst Substances 0.000 description 55
- 230000000052 comparative effect Effects 0.000 description 34
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 32
- 238000002360 preparation method Methods 0.000 description 25
- 239000007800 oxidant agent Substances 0.000 description 22
- 230000008569 process Effects 0.000 description 19
- 230000001590 oxidative effect Effects 0.000 description 18
- 230000005611 electricity Effects 0.000 description 17
- 229910052697 platinum Inorganic materials 0.000 description 16
- -1 ethynyl compound Chemical class 0.000 description 15
- 239000002243 precursor Substances 0.000 description 15
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 12
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium persulfate Chemical compound [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 description 12
- 229910001870 ammonium persulfate Inorganic materials 0.000 description 12
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 11
- 230000003647 oxidation Effects 0.000 description 11
- 238000007254 oxidation reaction Methods 0.000 description 11
- 239000005518 polymer electrolyte Substances 0.000 description 11
- 229920001940 conductive polymer Polymers 0.000 description 10
- 229920005989 resin Polymers 0.000 description 10
- 239000011347 resin Substances 0.000 description 10
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 description 9
- 230000003247 decreasing effect Effects 0.000 description 9
- 239000012528 membrane Substances 0.000 description 9
- 239000011230 binding agent Substances 0.000 description 8
- 229910052751 metal Inorganic materials 0.000 description 8
- 239000002184 metal Substances 0.000 description 8
- 239000002952 polymeric resin Substances 0.000 description 8
- 238000006722 reduction reaction Methods 0.000 description 8
- 239000001257 hydrogen Substances 0.000 description 7
- 229910052739 hydrogen Inorganic materials 0.000 description 7
- 239000012299 nitrogen atmosphere Substances 0.000 description 7
- 229920002239 polyacrylonitrile Polymers 0.000 description 7
- 239000002904 solvent Substances 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000006229 carbon black Substances 0.000 description 6
- 229910021393 carbon nanotube Inorganic materials 0.000 description 6
- 239000002041 carbon nanotube Substances 0.000 description 6
- 238000005341 cation exchange Methods 0.000 description 6
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 6
- 239000002105 nanoparticle Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 5
- 239000003638 chemical reducing agent Substances 0.000 description 5
- 229920001577 copolymer Polymers 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 5
- 238000002484 cyclic voltammetry Methods 0.000 description 5
- 238000007720 emulsion polymerization reaction Methods 0.000 description 5
- 229910021389 graphene Inorganic materials 0.000 description 5
- 229910002804 graphite Inorganic materials 0.000 description 5
- 239000010439 graphite Substances 0.000 description 5
- 229910052700 potassium Inorganic materials 0.000 description 5
- 229910052707 ruthenium Inorganic materials 0.000 description 5
- 229920003002 synthetic resin Polymers 0.000 description 5
- DZLFLBLQUQXARW-UHFFFAOYSA-N tetrabutylammonium Chemical compound CCCC[N+](CCCC)(CCCC)CCCC DZLFLBLQUQXARW-UHFFFAOYSA-N 0.000 description 5
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 4
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 4
- 239000012298 atmosphere Substances 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 239000011247 coating layer Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000005087 graphitization Methods 0.000 description 4
- 239000002070 nanowire Substances 0.000 description 4
- 229910052759 nickel Inorganic materials 0.000 description 4
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 4
- 239000004810 polytetrafluoroethylene Substances 0.000 description 4
- VDZOOKBUILJEDG-UHFFFAOYSA-M tetrabutylammonium hydroxide Chemical compound [OH-].CCCC[N+](CCCC)(CCCC)CCCC VDZOOKBUILJEDG-UHFFFAOYSA-M 0.000 description 4
- 229910052721 tungsten Inorganic materials 0.000 description 4
- 239000004215 Carbon black (E152) Substances 0.000 description 3
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 3
- 239000002033 PVDF binder Substances 0.000 description 3
- 229910000929 Ru alloy Inorganic materials 0.000 description 3
- 229910052804 chromium Inorganic materials 0.000 description 3
- 238000009792 diffusion process Methods 0.000 description 3
- 239000004744 fabric Substances 0.000 description 3
- 229930195733 hydrocarbon Natural products 0.000 description 3
- 150000002430 hydrocarbons Chemical class 0.000 description 3
- 229920000554 ionomer Polymers 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 229910052744 lithium Inorganic materials 0.000 description 3
- CFQCIHVMOFOCGH-UHFFFAOYSA-N platinum ruthenium Chemical compound [Ru].[Pt] CFQCIHVMOFOCGH-UHFFFAOYSA-N 0.000 description 3
- 229920001643 poly(ether ketone) Polymers 0.000 description 3
- 229920001721 polyimide Polymers 0.000 description 3
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 3
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 238000001228 spectrum Methods 0.000 description 3
- 125000000542 sulfonic acid group Chemical group 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- 229910052718 tin Inorganic materials 0.000 description 3
- 229910052720 vanadium Inorganic materials 0.000 description 3
- HYZJCKYKOHLVJF-UHFFFAOYSA-N 1H-benzimidazole Chemical compound C1=CC=C2NC=NC2=C1 HYZJCKYKOHLVJF-UHFFFAOYSA-N 0.000 description 2
- 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 2
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 2
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 2
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 2
- 229920000557 Nafion® Polymers 0.000 description 2
- 229910000820 Os alloy Inorganic materials 0.000 description 2
- 229910001252 Pd alloy Inorganic materials 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical group OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000004696 Poly ether ether ketone Substances 0.000 description 2
- 239000004695 Polyether sulfone Substances 0.000 description 2
- 239000004697 Polyetherimide Substances 0.000 description 2
- 239000004734 Polyphenylene sulfide Substances 0.000 description 2
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 238000004220 aggregation Methods 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 125000002843 carboxylic acid group Chemical group 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 238000004132 cross linking Methods 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 229910052731 fluorine Inorganic materials 0.000 description 2
- 239000011737 fluorine Substances 0.000 description 2
- 125000001153 fluoro group Chemical group F* 0.000 description 2
- 150000002431 hydrogen Chemical class 0.000 description 2
- 239000011229 interlayer Substances 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052750 molybdenum Inorganic materials 0.000 description 2
- 239000003345 natural gas Substances 0.000 description 2
- 229910052762 osmium Inorganic materials 0.000 description 2
- SYQBFIAQOQZEGI-UHFFFAOYSA-N osmium atom Chemical compound [Os] SYQBFIAQOQZEGI-UHFFFAOYSA-N 0.000 description 2
- IYZXTLXQZSXOOV-UHFFFAOYSA-N osmium platinum Chemical compound [Os].[Pt] IYZXTLXQZSXOOV-UHFFFAOYSA-N 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- ABLZXFCXXLZCGV-UHFFFAOYSA-N phosphonic acid group Chemical group P(O)(O)=O ABLZXFCXXLZCGV-UHFFFAOYSA-N 0.000 description 2
- 229920002492 poly(sulfone) Polymers 0.000 description 2
- 229920005569 poly(vinylidene fluoride-co-hexafluoropropylene) Polymers 0.000 description 2
- 229920006393 polyether sulfone Polymers 0.000 description 2
- 229920002530 polyetherether ketone Polymers 0.000 description 2
- 229920001601 polyetherimide Polymers 0.000 description 2
- 229920000069 polyphenylene sulfide Polymers 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000005086 pumping Methods 0.000 description 2
- 229910052703 rhodium Inorganic materials 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- 238000004611 spectroscopical analysis Methods 0.000 description 2
- 230000006641 stabilisation Effects 0.000 description 2
- 238000011105 stabilization Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- BFKJFAAPBSQJPD-UHFFFAOYSA-N tetrafluoroethene Chemical group FC(F)=C(F)F BFKJFAAPBSQJPD-UHFFFAOYSA-N 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- JMGNVALALWCTLC-UHFFFAOYSA-N 1-fluoro-2-(2-fluoroethenoxy)ethene Chemical compound FC=COC=CF JMGNVALALWCTLC-UHFFFAOYSA-N 0.000 description 1
- LDXJRKWFNNFDSA-UHFFFAOYSA-N 2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)-1-[4-[2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidin-5-yl]piperazin-1-yl]ethanone Chemical compound C1CN(CC2=NNN=C21)CC(=O)N3CCN(CC3)C4=CN=C(N=C4)NCC5=CC(=CC=C5)OC(F)(F)F LDXJRKWFNNFDSA-UHFFFAOYSA-N 0.000 description 1
- WBIQQQGBSDOWNP-UHFFFAOYSA-N 2-dodecylbenzenesulfonic acid Chemical compound CCCCCCCCCCCCC1=CC=CC=C1S(O)(=O)=O WBIQQQGBSDOWNP-UHFFFAOYSA-N 0.000 description 1
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 description 1
- XMWRBQBLMFGWIX-UHFFFAOYSA-N C60 fullerene Chemical compound C12=C3C(C4=C56)=C7C8=C5C5=C9C%10=C6C6=C4C1=C1C4=C6C6=C%10C%10=C9C9=C%11C5=C8C5=C8C7=C3C3=C7C2=C1C1=C2C4=C6C4=C%10C6=C9C9=C%11C5=C5C8=C3C3=C7C1=C1C2=C4C6=C2C9=C5C3=C12 XMWRBQBLMFGWIX-UHFFFAOYSA-N 0.000 description 1
- 229920000049 Carbon (fiber) Polymers 0.000 description 1
- FBPFZTCFMRRESA-FSIIMWSLSA-N D-Glucitol Natural products OC[C@H](O)[C@H](O)[C@@H](O)[C@H](O)CO FBPFZTCFMRRESA-FSIIMWSLSA-N 0.000 description 1
- FBPFZTCFMRRESA-JGWLITMVSA-N D-glucitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-JGWLITMVSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 239000004812 Fluorinated ethylene propylene Substances 0.000 description 1
- 229910002567 K2S2O8 Inorganic materials 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 description 1
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 1
- 238000001016 Ostwald ripening Methods 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 1
- 235000011613 Pinus brutia Nutrition 0.000 description 1
- 241000018646 Pinus brutia Species 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 238000001069 Raman spectroscopy Methods 0.000 description 1
- 229910021607 Silver chloride Inorganic materials 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 239000006230 acetylene black Substances 0.000 description 1
- 238000010306 acid treatment Methods 0.000 description 1
- 125000003545 alkoxy group Chemical group 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000004873 anchoring Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000005899 aromatization reaction Methods 0.000 description 1
- RWCCWEUUXYIKHB-UHFFFAOYSA-N benzophenone Chemical compound C=1C=CC=CC=1C(=O)C1=CC=CC=C1 RWCCWEUUXYIKHB-UHFFFAOYSA-N 0.000 description 1
- 239000012965 benzophenone Substances 0.000 description 1
- 150000001721 carbon Chemical class 0.000 description 1
- 239000004917 carbon fiber Substances 0.000 description 1
- 229920002301 cellulose acetate Polymers 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006356 dehydrogenation reaction Methods 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 229940113088 dimethylacetamide Drugs 0.000 description 1
- 238000003618 dip coating Methods 0.000 description 1
- SZXQTJUDPRGNJN-UHFFFAOYSA-N dipropylene glycol Chemical compound OCCCOCCCO SZXQTJUDPRGNJN-UHFFFAOYSA-N 0.000 description 1
- 238000007606 doctor blade method Methods 0.000 description 1
- 229940060296 dodecylbenzenesulfonic acid Drugs 0.000 description 1
- HQQADJVZYDDRJT-UHFFFAOYSA-N ethene;prop-1-ene Chemical group C=C.CC=C HQQADJVZYDDRJT-UHFFFAOYSA-N 0.000 description 1
- 229920001038 ethylene copolymer Polymers 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 229910003472 fullerene Inorganic materials 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910021397 glassy carbon Inorganic materials 0.000 description 1
- 238000007756 gravure coating Methods 0.000 description 1
- GEAWFZNTIFJMHR-UHFFFAOYSA-N hepta-1,6-diene Chemical compound C=CCCCC=C GEAWFZNTIFJMHR-UHFFFAOYSA-N 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002063 nanoring Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000010422 painting Methods 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 1
- 229920009441 perflouroethylene propylene Polymers 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 229920002493 poly(chlorotrifluoroethylene) Polymers 0.000 description 1
- 229920001197 polyacetylene Polymers 0.000 description 1
- 229920000412 polyarylene Polymers 0.000 description 1
- 229920001610 polycaprolactone Polymers 0.000 description 1
- 239000004632 polycaprolactone Substances 0.000 description 1
- 239000005023 polychlorotrifluoroethylene (PCTFE) polymer Substances 0.000 description 1
- 229920001470 polyketone Polymers 0.000 description 1
- 229920005594 polymer fiber Polymers 0.000 description 1
- 229920000417 polynaphthalene Polymers 0.000 description 1
- 235000019422 polyvinyl alcohol Nutrition 0.000 description 1
- 229920002451 polyvinyl alcohol 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
- 238000010248 power generation Methods 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000006479 redox reaction Methods 0.000 description 1
- 238000002407 reforming Methods 0.000 description 1
- 239000005871 repellent Substances 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 238000007363 ring formation reaction Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000007650 screen-printing Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 1
- 239000000600 sorbitol Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Images
Classifications
-
- 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
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
- H01M4/92—Metals of platinum group
- H01M4/925—Metals of platinum group supported on carriers, e.g. powder carriers
- H01M4/926—Metals of platinum group supported on carriers, e.g. powder carriers on carbon or graphite
-
- 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
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
-
- 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
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/96—Carbon-based electrodes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M2008/1095—Fuel cells with polymeric electrolytes
-
- 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
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
- H01M4/92—Metals of platinum group
-
- 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
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
- H01M4/92—Metals of platinum group
- H01M4/921—Alloys or mixtures with metallic elements
-
- 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
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Definitions
- Embodiments relate to a support for a fuel cell, method of preparing the same, an electrode for a fuel cell, a membrane-electrode assembly for a fuel cell including the same, and a fuel cell system including the same.
- a fuel cell is a power generation system for producing electrical energy through an electrochemical redox reaction of an oxidant and a fuel such as hydrogen or a hydrocarbon-based material such as methanol, ethanol, natural gas, and the like.
- Such a fuel cell is a clean energy source that may replace fossil fuels.
- a fuel cell may include a stack composed of unit cells, and may produce various ranges of power output. The fuel cell has a four to ten times higher energy density than a small lithium battery and thus, has been high-lighted as a small portable power source.
- Representative exemplary fuel cells include a polymer electrolyte membrane fuel cell (PEMFC) and a direct oxidation fuel cell (DOFC).
- the direct oxidation fuel cell includes a direct methanol fuel cell which uses methanol as a fuel.
- the polymer electrolyte fuel cell has advantages of high energy density and high power, and a direct oxidation fuel cell has lower energy density than that of the polymer electrolyte fuel cell, but has advantages of easy handling of the liquid-type fuel, a low operation temperature, and no need for an additional fuel reforming processor.
- a stack that substantially generates electricity includes several to scores of unit cells stacked adjacent to one another, and each unit cell is composed of a membrane-electrode assembly (MEA) and a separator (also referred to as a bipolar plate).
- MEA membrane-electrode assembly
- the membrane-electrode assembly is composed of an anode (also referred to as a “fuel electrode” or an “oxidation electrode”) and a cathode (also referred to as an “air electrode” or a “reduction electrode”) that are separated by a polymer electrolyte membrane.
- Electricity is generated as follows. A fuel is supplied to the anode and adsorbed on catalysts of the anode and then, oxidized to produce protons and electrons. The electrons are transferred into the cathode via an external circuit, while the protons are transferred into the cathode through the polymer electrolyte membrane. In addition, an oxidant is supplied to the cathode. Then, the oxidant reacts with the protons and the electrons on the catalysts of the cathode to produce electricity along with water.
- Embodiments are directed to a support for a fuel cell including a substrate including highly crystalline carbon, and a crystalline carbon layer on the substrate.
- the crystalline carbon layer may have a thickness of about 1 nm to about 40 nm.
- the highly crystalline carbon may have a Raman spectrum intensity ratio between a (1360) plane and a (1580) plane, I D /I G ((I(1360 cm ⁇ 1 )/I(1580 cm ⁇ 1 )) of about 0.24 to about 0.91.
- the highly crystalline carbon may include carbon nanotube, carbon nanowire, heat-treated carbon black, graphite, graphene, or a combination thereof.
- Embodiments are also directed to a method of preparing the support for a fuel cell including adding a monomer for a graphitizable polymer to a highly crystalline carbon liquid to prepare a mixture, adding a polymerization initiator to the mixture to perform polymerization and prepare a polymerization product, stabilizing the polymerization product to prepare a stabilized product, first heat-treating the stabilized product to provide a first heat-treated product, second heat-treating and carbonizing the first heat-treated product to provide a resultant, and third heat-treating and graphitizing the resultant.
- the polymerization product may include highly crystalline carbon and a carbon layer.
- the carbon layer may have a coating ratio represented by the following Equation 1 of about 100% to about 800%.
- the first heat-treating may be performed at about 300° C. to about 700° C.
- the stabilizing may be performed at about 220° C. to about 280° C.
- the second heat-treating may include a first heating stage at about 400° C. to about 800° C. and second heating stage at about 800° C. to about 1200° C.
- the third heat-treating may be performed at about 1200° C. to about 2500° C.
- Embodiments are also directed to an electrode for a fuel cell including an electrode substrate, and a catalyst layer on the electrode substrate, the catalyst layer including the support as disclosed above and an active metal supported on the support.
- the active metal may include platinum, ruthenium, osmium, a platinum-ruthenium alloy, a platinum-osmium alloy, a platinum-palladium alloy, or a platinum-M alloy, wherein M is at least one transition element selected from Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sn, Mo, W, Rh, and Ru.
- Embodiments are also directed to a membrane-electrode assembly for a fuel cell including a cathode and an anode facing each other and a polymer electrolyte membrane between the cathode and anode. At least one of the cathode and anode may be the electrode disclosed above.
- Embodiments are also directed to fuel cell system including at least one electricity generating element including the membrane-electrode assembly disclosed above and a separator positioned at each side of the membrane-electrode assembly, a fuel supplier that supplies the electricity generating element with a fuel, and an oxidant supplier that supplies the electricity generating element with an oxidant.
- FIG. 1 illustrates a schematic view showing a fuel cell system according to one embodiment
- FIG. 2 illustrates a TEM photograph of the support obtained from Example 1
- FIG. 3 illustrates a graph showing FT-IR of the support precursor obtained from Preparation Example 1;
- FIG. 4 illustrates a graph showing XPS (X-ray photoelectron spectroscopy) survey spectra of the support obtained from Comparative Example 1 and the support precursor obtained from Preparation Example 1;
- FIG. 5 illustrates a high-resolution transmission electron microscope (HR-TEM) photograph of the catalyst obtained by supporting Pt nanoparticles in the support obtained from Example 2;
- FIG. 6 illustrates a high-resolution transmission electron microscope (HR-TEM) photograph of the support obtained from Example 2;
- FIG. 7 illustrates a graph showing XPS C1s core-level spectra of the carbon support obtained from Example 1 (a); and FIG. 7B is a graph showing XPS Pt4f core-level spectra of the catalyst obtained from Example 3(b);
- FIG. 8 illustrates a graph showing a decreasing rate of electrochemical active area of a half cell obtained using the catalysts obtained from Examples 3, 4 and Comparative Examples 4 to 6;
- FIG. 9 illustrates a graph showing an electrochemical surface area of a half cell obtained using the catalysts obtained from Examples 3, 4 and Comparative Examples 4 to 6;
- FIG. 10 illustrates a graph showing a Raman spectrum of the supports obtained from Examples 1 and 2 and Comparative Examples 1, 2 and the catalysts obtained from Comparative Example 6 and a Control;
- FIG. 11 illustrates a graph showing the Raman spectrum area ratio and intensity ratio of supports obtained from Examples 1 to 2 and Comparative Examples 1, 2 and the catalysts obtained from Comparative Example 6 and a Control.
- One embodiment provides a support for a fuel cell that includes a substrate including highly crystalline carbon and a crystalline carbon layer disposed on the substrate.
- the highly crystalline carbon may be carbon nanotube, carbon nanowire, heat-treated carbon black, graphite, graphene, or a combination thereof.
- the heat-treated carbon black may be prepared by heat-treating the carbon black at about 1000° C. to about 2500° C. for about 30 minutes to about 1 hour.
- the heat treatment atmosphere may be N 2 , Ar, or a combination thereof.
- the heat treatment may be performed at a heat-up rate of about 1° C./min to about 6° C./min.
- the heat treatment may be performed in 3 steps from the low temperature to the high temperature. In this case, the heat-up rate may be changed in each step so that the heat-up rate is decreased as increasing the temperature.
- the thickness of the substrate including highly crystalline carbon and the crystalline carbon layer may be appropriately adjusted according to the kind of carbon that is used.
- the crystalline carbon layer may have a thickness of about 1 nm to about 40 nm.
- the highly crystalline carbon may have a Raman spectrum intensity ratio between a (1360) plane and a (1580) plane, I D /I G ((I(1360 cm ⁇ 1 )/I(1580 cm ⁇ 1 )) of about 0.24 to about 0.91.
- the highly crystalline carbon has the Raman spectrum intensity ratio within this range, the high crystalline and the high graphitization degree may be obtained, so as to provide advantages of low carbon oxidation rate.
- the highly crystalline carbon may have an interlayer spacing (d002) of a (002) plane of 3.35 ⁇ to 3.55 ⁇ .
- the support according to one embodiment has a structure that includes a highly crystalline carbon substrate and a crystalline carbon layer disposed on the substrate. Such a structure may have improved durability.
- the crystalline carbon layer may be formed from the graphitizable polymer, and a functionalized carbon structure having a high graphitization degree may be formed while crystallizing the graphitizable polymer. Accordingly, resistance to oxidation corrosion may be improved if the functionalized carbon has a high crystallinity.
- the support according to one embodiment may effectively suppress the support corrosion if fewer defects are present on the surface of support, and the support may have improved stability due to the high resistance.
- the gaps between re bond of the functional carbon acts as an anchoring center
- the adherence between the support and the catalyst may be increased, and the support aggregation may be suppressed.
- the stable structure and the anchoring site of the functionalized carbon may suppress the phenomenon that the catalyst is aggregated or detached from the support, so as to prevent or reduce catalyst corrosion.
- a Pt/C catalyst supporting Pt nanoparticle in the carbon support is widely used as a catalyst for a fuel cell, but the electrochemical surface area (ECSA) of Pt is shapely decreased by the phenomenon of carbon support corrosion, Pt nanoparticle decomposition, Ostwald ripening, and aggregation. As a result, the durability of the catalyst may remarkably deteriorate.
- ECSA electrochemical surface area
- the support may have improved durability, such that deterioration may be prevented or hindered.
- Another embodiment provides a method of preparing the support for a fuel cell.
- the method includes adding a monomer for a graphitizable polymer to a highly crystalline carbon liquid (for example, a highly crystalline carbon dissolved or suspended in a liquid) to prepare a mixture, adding a polymerization initiator to the mixture to perform polymerization and prepare a polymerization product, stabilizing the polymerization product to prepare a stabilized product, first heat-treating the stabilized product, second heat-treating and carbonizing the first heat-treated product, and third heat-treating and graphitizing the resultant.
- a method of preparing the support for a fuel cell according to one embodiment is described in detail.
- a precursor for forming a graphitizable polymer is added to the highly crystalline carbon liquid.
- the highly crystalline carbon liquid may be prepared by adding a highly crystalline carbon in a solvent.
- the carbon liquid may be a carbon suspension.
- the ultrasonic wave treatment may be carried out. The ultrasonic wave treatment may be performed for about 5 minutes to about 60 minutes.
- the highly crystalline carbon may be added to the solvent in an amount of about 1 wt % to about 70 wt % based on 100 percent by weight of the solvent.
- the highly crystalline carbon may be carbon nanotube, carbon nanowire, heat-treated carbon black, graphite, graphene, or a combination thereof.
- the precursor for forming a graphitizable polymer may be a diarylacetylene derivative, an alkyl derivative, an alkoxy derivative (benzophenone, phosphate), a 1,6-heptadiene-based compound, a dihalohetero compound, an ethynyl compound or a combination thereof.
- the precursor be any precursor being capable of forming of a polymer of polyacrylonitrile, polycaprolactone, polyvinylene, polynaphthalene, polyimide, polyketone, polyarylene derivative, polyarylene-vinylene or a combination thereof.
- a polymerization initiator may be added to the mixture to be polymerized.
- the polymerization initiator may be ammonium persulfate ((NH 4 ) 2 S 2 O 8 ), potassium persulfate (K 2 S 2 O 8 ), azobisisobutyronitrile (C 8 H 12 N 4 ), or a combination thereof, as examples.
- the polymerization initiator may be added in a suitable amount for initiating the polymerization reaction of the monomer for a graphitizable polymer.
- the polymerization may be performed by agitating under an atmosphere of nitrogen, argon, or a combination thereof at a temperature of about 0° C. to about 70° C. for about 1 hour to about 48 hours.
- the polymerization product may be cleaned according to a general washing process.
- the polymerization product may be vacuum-dried at about 60° C. to about 120° C.
- the polymerization product includes highly crystalline carbon and a carbon layer.
- the carbon layer may be formed on the highly crystalline carbon.
- the carbon layer may have a coating ratio represented by the following Equation 1 of about 100% to about 800%. In an implementation, the carbon layer may have a coating ratio of about 110% to about 800%.
- the carbon layer may be uniformly coated on the substrate including the highly crystalline carbon, and the highly crystalline graphitic layer structure may be easily formed without deteriorating the characteristics of high crystalline carbon.
- the stabilizing may include a chemical reaction such as crosslinking, oxidation, aromatization, dehydrogenation, or cyclization of graphitizable polymer.
- the stabilizing may be performed with a rising temperature at a heat-up rate of about 3° C./min to about 5° C./min under the air atmosphere to a final temperature of about 220° C. to about 280° C. and then continuing at the final temperature for about 30 minutes to about 2 hours.
- the graphitizable polymer may adsorb oxygen from the air as part of the cycling and the crosslinking linkage, so as to provide a thermally stable ladder polymer structure in the following carbonizing process according to the reaction. If the temperature of the stabilizing process is lower than the range, the reaction may occur too slowly, and the stabilization may be incompletely performed, so as to deteriorate the carbon physical properties. On the other hand, if the temperature of the stabilization process is higher than the range, the graphitizable polymer may be excessively heated to be melted or combusted, which is unfavorable.
- the stabilized substrate may be subjected to a first heat-treating process.
- the first heat-treating process may be performed under a N 2 or Ar atmosphere at a heat-up rate of about 3° C./min to about 5° C./min and maintained at about 300° C. to about 700° C. for about 30 minutes to about 6 hours.
- the carbon content may be increased to be greater than or equal to about 90 wt % by exhausting various gases, or a three dimensional carbon structure having molecular and fibrillar orientation may be formed.
- the polymer chain maybe rearranged according to the first heat-treatment so that the parallel molecular chain may form a three dimensional bond.
- the effects according to the first heat-treating process may be further effectively obtained when the heat-treatment is performed under the above-mentioned conditions.
- the first heat-treated substrate may be subjected to a second heat-treating process to be carbonized.
- the polymer coated on the substrate may be carbonized.
- the second heat-treating process includes a first step of heating at about 400° C. to about 800° C. and a second step of heating at about 800° C. to about 1200° C.
- structures such as graphite oxide may be removed, and carbon with an sp 2 structure may be developed.
- the substrate that has undergone the carbonizing process may be subjected to a third heat-treating process to be graphitized.
- the carbonized polymer is finally graphitized to provide graphite, which is a crystalline carbon layer, on the substrate.
- the third heat-treating process may be performed by heating at about 1200° C. to about 2500° C.
- the formed graphitic layer structure may be further developed and arranged, and graphene sheets may be stacked together well. Accordingly, a uniform graphitic layer may be provided that may slow the kinetics of carbon oxidation to improve the anti-corrosion properties of carbon.
- the high temperature graphitization process may remove an amorphous phase to enhance the graphitized structure arrangement, so that a mesoporous channel aligned with graphene layers may be well developed.
- Another embodiment provides a catalyst for a fuel cell including the support and an active metal supported on the support.
- the active metal may be platinum, ruthenium, osmium, a platinum-ruthenium alloy, a platinum-osmium alloy, a platinum-palladium alloy, a platinum-M alloy (M is at least one transition element selected from Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sn, Mo, W, Rh, and Ru), or a combination thereof.
- the catalyst according to one embodiment may be used in an anode and/or a cathode.
- the anode and cathode may include the same catalyst.
- a direct oxidation fuel cell may include a platinum-ruthenium alloy catalyst as an anode catalyst in order to prevent catalyst poisoning in the anode reaction.
- the catalyst may include one selected from Pt, Pt/Ru, Pt/W, Pt/Ni, Pt/Sn, Pt/Mo, Pt/Pd, Pt/Fe, Pt/Cr, Pt/Co, Pt/Ru/W, Pt/Ru/Mo, Pt/Ru/V, Pt/Fe/Co, Pt/Ru/Rh/Ni, and Pt/Ru/Sn/W.
- the process of supporting the active metal in a support may be carried out by any suitable process.
- Yet another embodiment provides an electrode for a fuel cell including a catalyst layer including the catalyst and an electrode substrate.
- the catalyst layer may further include a binder resin to improve its adherence and proton transfer properties.
- the binder resin may be a proton conductive polymer resin.
- the binder resin may include a polymer resin having a cation exchange group selected from a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, a phosphonic acid group, and derivatives thereof at its side chain.
- the polymer resin may include at least one proton conductive polymer selected from a fluoro-based polymer, a benzimidazole-based polymer, a polyimide-based polymer, a polyetherimide-based polymer, a polyphenylenesulfide-based polymer, a polysulfone-based polymer, a polyethersulfone-based polymer, a polyetherketone-based polymer, a polyether-etherketone-based polymer, and a polyphenylquinoxaline-based polymer.
- a proton conductive polymer selected from a fluoro-based polymer, a benzimidazole-based polymer, a polyimide-based polymer, a polyetherimide-based polymer, a polyphenylenesulfide-based polymer, a polysulfone-based polymer, a polyethersulfone-based polymer, a polyetherketone-based polymer, a polyether-ether
- the hydrogen (H) in the cation exchange group of the proton conductive polymer may be substituted with Na, K, Li, Cs, or tetrabutylammonium.
- H in the cation exchange group of the terminal end of the proton conductive polymer side chain is substituted with Na or tetrabutylammonium
- NaOH or tetrabutylammonium hydroxide may be used during preparation of the catalyst composition, respectively.
- suitable compounds for the substitutions may be used.
- the binder resin may be used singularly or in combination.
- the binder resin may be used along with non-conductive polymers to improve adherence with a polymer electrolyte membrane.
- the binder resin may be used in a controlled amount.
- non-conductive polymers include at least one selected from polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkylvinylether copolymer (PFA), ethylene/tetrafluoroethylene (ETFE), ethylenechlorotrifluoro-ethylene copolymer (ECTFE), polyvinylidenefluoride, a polyvinylidenefluoride-hexafluoropropylene copolymer (PVdF-HFP), dodecylbenzenesulfonic acid, and sorbitol.
- PTFE polytetrafluoroethylene
- FEP tetrafluoroethylene-hexafluoropropylene copolymer
- PFA tetrafluoroethylene-perfluoroalkylvinylether copolymer
- ETFE ethylene/tetrafluor
- the electrode substrate plays a role of supporting an electrode and diffusing a fuel and an oxidant into a catalyst layer, so that the fuel and the oxidant may easily approach the catalyst layer.
- the electrode substrates may be formed from a material such as carbon paper, carbon cloth, carbon felt, or a metal cloth (a porous film composed of metal fiber or a metal film disposed on a surface of a cloth composed of polymer fibers), as examples.
- the electrode substrates may be treated with a fluorine-based resin to be water-repellent to prevent deterioration of diffusion efficiency due to water generated during operation of a fuel cell.
- the fluorine-based resin may be one selected from polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, polyperfluoroalkylvinylether, polyperfluorosulfonylfluoride alkoxyvinyl ether, fluorinated ethylene propylene, polychlorotrifluoroethylene, and a copolymer thereof.
- the anode or cathode may further include a microporous layer on an electrode substrate.
- the microporous layer may include conductive powders with a certain particle diameter.
- the conductive material may include, but is not limited to, carbon powder, carbon black, acetylene black, activated carbon, a carbon fiber, fullerene, carbon nanotubes, carbon nanowires, carbon nanohorns, carbon nanorings, or combinations thereof.
- the microporous layer is formed by coating a composition including a conductive powder, a binder resin, and a solvent on the conductive substrate.
- the binder resin may include, for example, polytetrafluoroethylene, polyvinylidenefluoride, polyhexafluoropropylene, polyperfluoroalkylvinylether, polyperfluorosulfonylfluoride, alkoxyvinyl ether, polyvinylalcohol, cellulose acetate, or a copolymer thereof.
- the solvent may include, for example, an alcohol such as ethanol, isopropyl alcohol, n-propyl alcohol, butanol, etc., water, dimethyl acetamide, dimethyl sulfoxide, N-methylpyrrolidone, or tetrahydrofuran.
- the coating method may include, for example, screen printing, spray coating, doctor blade methods, gravure coating, dip coating, silk screening, painting, etc., depending on the viscosity of the composition.
- a membrane-electrode assembly for a fuel cell including the electrode as either one of a cathode or an anode.
- the membrane-electrode assembly for a fuel cell includes a cathode and an anode facing each other, and a polymer electrolyte membrane interposed between the cathode and anode.
- the polymer electrolyte membrane may be any generally-used polymer electrolyte membrane made of a proton conductive polymer resin.
- the proton conductive polymer resin may be a polymer resin having a cation exchange group selected from a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, a phosphonic acid group, and derivatives thereof, at its side chain.
- the polymer resin examples include at least one selected from a fluoro-based polymer, a benzimidazole-based polymer, a polyimide-based polymer, a polyetherimide-based polymer, a polyphenylenesulfide-based polymer, a polysulfone-based polymer, a polyethersulfone-based polymer, a polyetherketone-based polymer, a polyether-etherketone-based polymer, and a polyphenylquinoxaline-based polymer.
- the polymer resin may include poly(perfluorosulfonic acid) (commercially available as “NAFION”), poly(perfluorocarboxylic acid), a copolymer of tetrafluoroethylene having a sulfonic acid group and fluorovinylether, defluorinated polyetherketone sulfide, an aryl ketone, or poly[(2,2′-m-phenylene)-5,5′-bibenzimidazole].
- poly(perfluorosulfonic acid) commercially available as “NAFION”
- poly(perfluorocarboxylic acid) a copolymer of tetrafluoroethylene having a sulfonic acid group and fluorovinylether, defluorinated polyetherketone sulfide, an aryl ketone, or poly[(2,2′-m-phenylene)-5,5′-bibenzimidazole].
- the hydrogen (H) in the cation exchange group of the proton conductive polymer may be substituted with Na, K, Li, Cs, or tetrabutylammonium.
- H in the cation exchange group of the terminal end of the proton conductive polymer side chain is substituted with Na or tetrabutylammonium
- NaOH or tetrabutylammonium hydroxide may be used during preparation of the catalyst composition, respectively.
- suitable compounds for the substitutions may be used.
- Such a Na, K, Li, Cs, or tetrabutylammonium may be converted into a proton during a subsequent acid treatment of a catalyst layer, and thus, a proton form (H + -form) polymer electrolyte membrane may be provided.
- Another embodiment provides a fuel cell system including at least one electricity generating element, a fuel supplier, and an oxidant supplier.
- the electricity generating element may include the membrane-electrode assembly according to one embodiment and a separator (referred to as a bipolar plate).
- the electricity generating element may generate electricity through oxidation of a fuel and reduction of an oxidant.
- the fuel supplier may supply the electricity generating element with a fuel, while the oxidizing agent supplier may supply the electricity generating element with an oxidizing agent such as oxygen or air.
- the fuel may include liquid or gaseous hydrogen or a hydrocarbon fuel.
- the hydrocarbon fuel for example, may be methanol, ethanol, propanol, butanol, or natural gas.
- FIG. 1 illustrates the schematic structure of a fuel cell system according to an embodiment, which will be described in details with the reference to this accompanying drawing as follows.
- FIG. 1 shows a fuel cell system supplying a fuel and an oxidizing agent to an electrical generating element using a pump
- the fuel cell system of the embodiment may include a structure wherein a fuel and an oxidant are provided by diffusion.
- a fuel system 1 of the embodiment may include at least one electricity generating element 3 that generates an electrical energy by oxidation of a fuel and reduction of an oxidizing agent, a fuel supplier 5 that supplies the fuel, and an oxidant supplier 7 that supplies an oxidant to the electricity generating element 3 .
- the fuel supplier 5 may be equipped with a tank 9 , which stores fuel, and a pump 11 , which is connected therewith.
- the fuel pump 11 may supply fuel stored in the tank 9 with a predetermined pumping power.
- the oxidant supplier 7 which supplies the electricity generating element 3 with an oxidant, may be equipped with at least one oxidant pump 13 for supplying an oxidant with a predetermined pumping power.
- the electricity generating element 3 may include a membrane-electrode assembly 17 , which oxidizes hydrogen or a fuel and reduces an oxidant, and separators 19 and 19 ′ that are respectively positioned at opposite sides of the membrane-electrode assembly and that supply hydrogen or a fuel, and an oxidant, respectively.
- the stack 15 may be provided by stacking at least one of the electricity generating elements 3 .
- the polymerized product was centrifuged and washed with deionized water and ethanol. Then, the washed product was vacuum-dried at 60° C. to provide a carbon substrate coated with polyacrylonitile (PAN) layer as a support precursor.
- PAN polyacrylonitile
- a support precursor in the form of a carbon substrate coated with a polyacrylonitrile layer, was prepared in accordance with the same procedure as in Preparation Example 1, except that after the 1.08 g of ammonium persulfate ((NH 4 ) 2 S 2 O 8 ) was added, the agitating under the nitrogen atmosphere at 65° C. was carried out for 1 hour to provide the emulsion polymerization.
- ammonium persulfate (NH 4 ) 2 S 2 O 8 )
- ammonium persulfate (NH 4 ) 2 S 2 O 8 )
- ammonium persulfate (NH 4 ) 2 S 2 O 8 )
- ammonium persulfate (NH 4 ) 2 S 2 O 8 )
- the carbon substrate formed with the PAN coating layer obtained from Preparation Example 1 was stabilized at a heat-up rate of 3° C./min at 280° C. for 1 hour to provide a carbon support coated with a PAN layer.
- the carbon substrate formed with the PAN coating layer obtained from Preparation Example 1 was stabilized at a heat-up rate of 3° C./min at 280° C. for 1 hour and subjected to a first heat-treatment under a N 2 atmosphere at a heat-up rate of 3° C./min at 400° C. for 2 hours. Then, the first heat-treated product was subjected to a second heat-treatment to provide a carbon support coated with a PAN layer. The second heat-treatment was performed with a first step of heating at 450° C. and second step of heating at 800° C.
- the carbon substrate formed with a PAN coating layer obtained Preparation Example 1 was stabilized at 280° C. for 1 hour with a heat-up rate of 3° C./min, and the obtained product subjected to a first heat-treatment at a heat-up rate of 3° C./min under an N 2 atmosphere at 400° C. for 2 hours, and the first-treated product was subjected to a second heat-treatment.
- the second heat-treatment was performed with a first step of heating at 450° C. and a second step of heating at 800° C. Then the second heat-treated product was subjected to a third heat-treatment at 2000° C. to provide a carbon support coated with a crystalline carbon layer.
- the crystalline carbon has an interlayer spacing (d002) of a (002) plane of 3.4 ⁇ .
- a carbon support coated with the crystalline carbon layer was fabricated in accordance with the same procedure as in Example 1, except that the third heat-treatment was performed at 2500° C.
- a carbon support coated with a PAN layer was fabricated in accordance with the same procedure as in Comparative Example 2, except that the second step of heating during the second heat-treatment was performed at 1000° C.
- the support precursor obtained from Preparation Example 1 was analyzed by FT-IR, and the results are shown in FIG. 3 .
- the support precursor obtained from Preparation Example 1 showed a strong peak corresponding to the stretching vibration of a CN group around 2240 cm ⁇ 1 . Thereby, it may be determined that the polyacrylonitrile (PAN) chain was formed on the crystalline carbon surface according to the chemical polymerization.
- PAN polyacrylonitrile
- the support obtained from the Comparative Example 1 and the support precursor obtained from Preparation Example 1 were analyzed by X-ray photoelectron spectroscopy (XPS), and the results are shown in FIG. 4 .
- XPS X-ray photoelectron spectroscopy
- FIG. 4 in addition to a C1s (about 285 eV) signal and an O1s (about 532 eV) signal, a N1s (about 399 eV) signal was also observed. From the results, it may be determined that the PAN coating layer introduced by the chemical polymerization was formed on the surface of crystalline carbon.
- FIG. 5 shows an HR-TEM image of the support obtained from Example 2. As shown in FIG. 6 , it may be seen that the obtained support had a structure of a substrate and a crystalline carbon layer disposed on the substrate.
- a catalyst for a fuel cell was fabricated by supporting Pt on the support obtained from Comparative Example 1 according to the chemical reduction.
- a catalyst for a fuel cell was fabricated by supporting Pt on the support obtained from Comparative Example 2 according to the chemical reduction.
- a catalyst for a fuel cell was fabricated by supporting Pt on the support obtained from Example 1 according to the chemical reduction.
- a catalyst for a fuel cell was fabricated by supporting Pt on the support obtained from Example 2 according to the chemical reduction.
- a catalyst (Pt/CNT) for a fuel cell was fabricated by supporting Pt on a carbon nanotube support formed with no carbon layer according to the chemical reduction.
- the carbon support obtained from Example 1 was analyzed by high resolution XPS C1s core-level spectroscopy, and the results are shown in (a) of FIG. 7 .
- the catalyst obtained from Example 3 was measured by high resolution XPS Pt4f core-level spectroscopy, and the results are shown in (b) of FIG. 7 .
- the decreasing ratio of the electrochemical active surface area after carrying out the CV compared to the initial electrochemical active surface area before carrying out the CV was calculated in terms of a percentage (%), and the results are shown in FIG. 8 .
- the CV test was performed by using a potentiostat (VSP, Bio-Logic SA), and a rotation control (Pine) in a setup of a temperature controller standard three-compartment electrode. In this case, a Pt-mesh electrode and an Ag/AgCl electrode were used as a counter electrode and a reference electrode, respectively.
- the electrochemical active surface area was calculated as the average of the peak area of hydrogen adsorption and desorption excepting the double layer charge values. Using an N 2 -saturated 0.1M HClO 4 solution, cycles were repeated at 0.6V to 1.4V for 1000 times, and ECSA was measured in each 100 cycles at a scan rate of 20 mW/s.
- the decreasing ratio of electrochemical active surface area of Examples 3 and 4 was less than that of Comparative Examples 4 to 6. Particularly, it may be determined that, in the case of Example 4, the electrochemical active surface area barely decreased.
- the half-cell was measured with respect to electrochemical surface area, and the results are shown in FIG. 9 .
- FIG. 9 it may be determined that the catalysts of Examples 3 and 4 had a significantly smaller decreasing ratio of electrochemical surface area than the catalysts of Comparative Examples 4 to 6. Particularly, it may be determined that the electrochemical surface area was barely decreased even after the 1000th cycle in Example 4. Accordingly, it may be estimated that the catalysts of Examples 3 and 4 had superior electrochemical stability and durability to those of Comparative Examples 4 to 6.
- the supports obtained from Examples 1 and 2 and Comparative Examples 1 and 2 were analyzed by Raman spectroscopy, and the results are shown in FIG. 10 .
- the catalyst according to Comparative Example 6 and a Control including only CNT were measured for Raman spectrum, and the results are also shown in FIG. 10 .
- the similar results are shown in all of Examples 1 and 2 and Comparative Examples 1, 2, 6, and CNT, so it may be determined that the support according to Examples 1 and 2 maintained a similar structure to those of the conventional supports.
- the supports of Examples 1 and 2 to Comparative Examples 1 and 2, and, for the comparison, the catalyst obtained from Comparative Example 6 and the Control of CNT were measured to determine a Raman spectrum area ratio (area integral ratio) and an intensity ratio at a (1580 cm ⁇ 1 ) plane and (1360 cm ⁇ 1 ) plane. From these measurements, the I D /I G area ratio (area (1360 cm ⁇ 1 )/area (1580 cm ⁇ 1 )) and the I D /I G intensity ratio (intensity (1360 cm ⁇ 1 )/intensity (1580 cm ⁇ 1 )) were calculated. The results are shown in FIG. 11 . From the results shown in FIG.
- the catalyst of Comparative Example 6 had a I D /I G area ratio of about 0.91, a I D /I G intensity ratio of about 0.69; and the catalysts of Control and Comparative Examples 1 and 2 had a I D /I G area ratio of about 0.78 to about 0.93, a I D /I G intensity ratio of about 0.53 to about 0.65.
- the catalysts of Examples 1 to 2 had a I D /I G area ratio of about 0.35, a I D /I G intensity ratio of about 0.24.
- the supports according to Examples 1 to 2 had a different Raman spectrum area ratio and intensity ratio from those of Comparative Examples 1, 2, 6 and the Control.
- the supports according to Examples 1 to 2 had a I D /I G area ratio of about 38%, a I D /I G intensity ratio of about 35% relative to the catalyst according to Comparative Example 6.
- embodiments provide a support for a fuel cell being capable of improving catalyst activity.
- Embodiments provide a method of preparing the support for a fuel cell.
- Embodiments provide an electrode for a fuel cell including the support for a fuel cell.
- Embodiments provide a membrane-electrode assembly for a fuel cell including the electrode.
- Embodiments provide a fuel cell system including the membrane-electrode assembly.
Abstract
A support for a fuel cell includes a substrate including highly crystalline carbon, and a crystalline carbon layer on the substrate.
Description
- This application is a divisional of U.S. application Ser. No. 14/069,853, filed on Nov. 1, 2013, which claims priority to Korean Patent Application No. 10-2013-0022990, filed on Mar. 4, 2013, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated by reference herein in its entirety.
- Embodiments relate to a support for a fuel cell, method of preparing the same, an electrode for a fuel cell, a membrane-electrode assembly for a fuel cell including the same, and a fuel cell system including the same.
- A fuel cell is a power generation system for producing electrical energy through an electrochemical redox reaction of an oxidant and a fuel such as hydrogen or a hydrocarbon-based material such as methanol, ethanol, natural gas, and the like.
- Such a fuel cell is a clean energy source that may replace fossil fuels. A fuel cell may include a stack composed of unit cells, and may produce various ranges of power output. The fuel cell has a four to ten times higher energy density than a small lithium battery and thus, has been high-lighted as a small portable power source.
- Representative exemplary fuel cells include a polymer electrolyte membrane fuel cell (PEMFC) and a direct oxidation fuel cell (DOFC). The direct oxidation fuel cell includes a direct methanol fuel cell which uses methanol as a fuel.
- The polymer electrolyte fuel cell has advantages of high energy density and high power, and a direct oxidation fuel cell has lower energy density than that of the polymer electrolyte fuel cell, but has advantages of easy handling of the liquid-type fuel, a low operation temperature, and no need for an additional fuel reforming processor.
- In the aforementioned fuel cell system, a stack that substantially generates electricity includes several to scores of unit cells stacked adjacent to one another, and each unit cell is composed of a membrane-electrode assembly (MEA) and a separator (also referred to as a bipolar plate). The membrane-electrode assembly is composed of an anode (also referred to as a “fuel electrode” or an “oxidation electrode”) and a cathode (also referred to as an “air electrode” or a “reduction electrode”) that are separated by a polymer electrolyte membrane.
- Electricity is generated as follows. A fuel is supplied to the anode and adsorbed on catalysts of the anode and then, oxidized to produce protons and electrons. The electrons are transferred into the cathode via an external circuit, while the protons are transferred into the cathode through the polymer electrolyte membrane. In addition, an oxidant is supplied to the cathode. Then, the oxidant reacts with the protons and the electrons on the catalysts of the cathode to produce electricity along with water.
- Embodiments are directed to a support for a fuel cell including a substrate including highly crystalline carbon, and a crystalline carbon layer on the substrate.
- The crystalline carbon layer may have a thickness of about 1 nm to about 40 nm.
- The highly crystalline carbon may have a Raman spectrum intensity ratio between a (1360) plane and a (1580) plane, ID/IG ((I(1360 cm−1)/I(1580 cm−1)) of about 0.24 to about 0.91.
- The highly crystalline carbon may include carbon nanotube, carbon nanowire, heat-treated carbon black, graphite, graphene, or a combination thereof.
- Embodiments are also directed to a method of preparing the support for a fuel cell including adding a monomer for a graphitizable polymer to a highly crystalline carbon liquid to prepare a mixture, adding a polymerization initiator to the mixture to perform polymerization and prepare a polymerization product, stabilizing the polymerization product to prepare a stabilized product, first heat-treating the stabilized product to provide a first heat-treated product, second heat-treating and carbonizing the first heat-treated product to provide a resultant, and third heat-treating and graphitizing the resultant.
- The polymerization product may include highly crystalline carbon and a carbon layer. The carbon layer may have a coating ratio represented by the following
Equation 1 of about 100% to about 800%. -
Coating ratio=[(W f −W 0)/W 0]×100(%) [Equation 1] -
- wherein, W0 denotes a weight (g) of highly crystalline carbon in the substrate, and
- Wf denotes a weight (g) of total polymerization product in the substrate and carbon layer.
- The first heat-treating may be performed at about 300° C. to about 700° C.
- The stabilizing may be performed at about 220° C. to about 280° C.
- The second heat-treating may include a first heating stage at about 400° C. to about 800° C. and second heating stage at about 800° C. to about 1200° C.
- The third heat-treating may be performed at about 1200° C. to about 2500° C.
- Embodiments are also directed to an electrode for a fuel cell including an electrode substrate, and a catalyst layer on the electrode substrate, the catalyst layer including the support as disclosed above and an active metal supported on the support.
- The active metal may include platinum, ruthenium, osmium, a platinum-ruthenium alloy, a platinum-osmium alloy, a platinum-palladium alloy, or a platinum-M alloy, wherein M is at least one transition element selected from Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sn, Mo, W, Rh, and Ru.
- Embodiments are also directed to a membrane-electrode assembly for a fuel cell including a cathode and an anode facing each other and a polymer electrolyte membrane between the cathode and anode. At least one of the cathode and anode may be the electrode disclosed above.
- Embodiments are also directed to fuel cell system including at least one electricity generating element including the membrane-electrode assembly disclosed above and a separator positioned at each side of the membrane-electrode assembly, a fuel supplier that supplies the electricity generating element with a fuel, and an oxidant supplier that supplies the electricity generating element with an oxidant.
- Features will become apparent to those of skill in the art by describing in detail exemplary embodiments with reference to the attached drawings in which:
-
FIG. 1 illustrates a schematic view showing a fuel cell system according to one embodiment; -
FIG. 2 illustrates a TEM photograph of the support obtained from Example 1; -
FIG. 3 illustrates a graph showing FT-IR of the support precursor obtained from Preparation Example 1; -
FIG. 4 illustrates a graph showing XPS (X-ray photoelectron spectroscopy) survey spectra of the support obtained from Comparative Example 1 and the support precursor obtained from Preparation Example 1; -
FIG. 5 illustrates a high-resolution transmission electron microscope (HR-TEM) photograph of the catalyst obtained by supporting Pt nanoparticles in the support obtained from Example 2; -
FIG. 6 illustrates a high-resolution transmission electron microscope (HR-TEM) photograph of the support obtained from Example 2; -
FIG. 7 illustrates a graph showing XPS C1s core-level spectra of the carbon support obtained from Example 1 (a); andFIG. 7B is a graph showing XPS Pt4f core-level spectra of the catalyst obtained from Example 3(b); -
FIG. 8 illustrates a graph showing a decreasing rate of electrochemical active area of a half cell obtained using the catalysts obtained from Examples 3, 4 and Comparative Examples 4 to 6; -
FIG. 9 illustrates a graph showing an electrochemical surface area of a half cell obtained using the catalysts obtained from Examples 3, 4 and Comparative Examples 4 to 6; -
FIG. 10 illustrates a graph showing a Raman spectrum of the supports obtained from Examples 1 and 2 and Comparative Examples 1, 2 and the catalysts obtained from Comparative Example 6 and a Control; and -
FIG. 11 illustrates a graph showing the Raman spectrum area ratio and intensity ratio of supports obtained from Examples 1 to 2 and Comparative Examples 1, 2 and the catalysts obtained from Comparative Example 6 and a Control. - Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary implementations to those skilled in the art.
- In the drawing figures, the dimensions of layers and regions may be exaggerated for clarity of illustration. It will also be understood that when a layer or element is referred to as being “on” another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. Further, it will be understood that when a layer is referred to as being “under” another layer, it can be directly under, and one or more intervening layers may also be present. In addition, it will also be understood that when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. Like reference numerals refer to like elements throughout.
- One embodiment provides a support for a fuel cell that includes a substrate including highly crystalline carbon and a crystalline carbon layer disposed on the substrate.
- The highly crystalline carbon may be carbon nanotube, carbon nanowire, heat-treated carbon black, graphite, graphene, or a combination thereof.
- If heat-treated carbon black is used, the heat-treated carbon black may be prepared by heat-treating the carbon black at about 1000° C. to about 2500° C. for about 30 minutes to about 1 hour. The heat treatment atmosphere may be N2, Ar, or a combination thereof. The heat treatment may be performed at a heat-up rate of about 1° C./min to about 6° C./min. When the heat treatment is performed with a rising temperature, the heat treatment may be performed in 3 steps from the low temperature to the high temperature. In this case, the heat-up rate may be changed in each step so that the heat-up rate is decreased as increasing the temperature.
- The thickness of the substrate including highly crystalline carbon and the crystalline carbon layer may be appropriately adjusted according to the kind of carbon that is used. According to an implementation, the crystalline carbon layer may have a thickness of about 1 nm to about 40 nm.
- In one embodiment, the highly crystalline carbon may have a Raman spectrum intensity ratio between a (1360) plane and a (1580) plane, ID/IG ((I(1360 cm−1)/I(1580 cm−1)) of about 0.24 to about 0.91. When the highly crystalline carbon has the Raman spectrum intensity ratio within this range, the high crystalline and the high graphitization degree may be obtained, so as to provide advantages of low carbon oxidation rate.
- In one embodiment, the highly crystalline carbon may have an interlayer spacing (d002) of a (002) plane of 3.35 Å to 3.55 Å.
- The support according to one embodiment has a structure that includes a highly crystalline carbon substrate and a crystalline carbon layer disposed on the substrate. Such a structure may have improved durability. The crystalline carbon layer may be formed from the graphitizable polymer, and a functionalized carbon structure having a high graphitization degree may be formed while crystallizing the graphitizable polymer. Accordingly, resistance to oxidation corrosion may be improved if the functionalized carbon has a high crystallinity. In addition, the support according to one embodiment may effectively suppress the support corrosion if fewer defects are present on the surface of support, and the support may have improved stability due to the high resistance. As the gaps between re bond of the functional carbon acts as an anchoring center, the adherence between the support and the catalyst may be increased, and the support aggregation may be suppressed. In addition, the stable structure and the anchoring site of the functionalized carbon may suppress the phenomenon that the catalyst is aggregated or detached from the support, so as to prevent or reduce catalyst corrosion.
- Generally, a Pt/C catalyst supporting Pt nanoparticle in the carbon support is widely used as a catalyst for a fuel cell, but the electrochemical surface area (ECSA) of Pt is shapely decreased by the phenomenon of carbon support corrosion, Pt nanoparticle decomposition, Ostwald ripening, and aggregation. As a result, the durability of the catalyst may remarkably deteriorate.
- According to an embodiment, the support may have improved durability, such that deterioration may be prevented or hindered.
- Another embodiment provides a method of preparing the support for a fuel cell. The method includes adding a monomer for a graphitizable polymer to a highly crystalline carbon liquid (for example, a highly crystalline carbon dissolved or suspended in a liquid) to prepare a mixture, adding a polymerization initiator to the mixture to perform polymerization and prepare a polymerization product, stabilizing the polymerization product to prepare a stabilized product, first heat-treating the stabilized product, second heat-treating and carbonizing the first heat-treated product, and third heat-treating and graphitizing the resultant. Hereinafter, a method of preparing the support for a fuel cell according to one embodiment is described in detail.
- First, a precursor for forming a graphitizable polymer is added to the highly crystalline carbon liquid.
- The highly crystalline carbon liquid may be prepared by adding a highly crystalline carbon in a solvent. The carbon liquid may be a carbon suspension. After adding the highly crystalline carbon into the solvent, the ultrasonic wave treatment may be carried out. The ultrasonic wave treatment may be performed for about 5 minutes to about 60 minutes.
- The highly crystalline carbon may be added to the solvent in an amount of about 1 wt % to about 70 wt % based on 100 percent by weight of the solvent.
- The highly crystalline carbon may be carbon nanotube, carbon nanowire, heat-treated carbon black, graphite, graphene, or a combination thereof.
- The precursor for forming a graphitizable polymer may be a diarylacetylene derivative, an alkyl derivative, an alkoxy derivative (benzophenone, phosphate), a 1,6-heptadiene-based compound, a dihalohetero compound, an ethynyl compound or a combination thereof. According to an implementation, the precursor be any precursor being capable of forming of a polymer of polyacrylonitrile, polycaprolactone, polyvinylene, polynaphthalene, polyimide, polyketone, polyarylene derivative, polyarylene-vinylene or a combination thereof.
- A polymerization initiator may be added to the mixture to be polymerized. The polymerization initiator may be ammonium persulfate ((NH4)2S2O8), potassium persulfate (K2S2O8), azobisisobutyronitrile (C8H12N4), or a combination thereof, as examples. The polymerization initiator may be added in a suitable amount for initiating the polymerization reaction of the monomer for a graphitizable polymer.
- The polymerization may be performed by agitating under an atmosphere of nitrogen, argon, or a combination thereof at a temperature of about 0° C. to about 70° C. for about 1 hour to about 48 hours.
- The polymerization product may be cleaned according to a general washing process. In addition, the polymerization product may be vacuum-dried at about 60° C. to about 120° C.
- The polymerization product includes highly crystalline carbon and a carbon layer. The carbon layer may be formed on the highly crystalline carbon. The carbon layer may have a coating ratio represented by the following
Equation 1 of about 100% to about 800%. In an implementation, the carbon layer may have a coating ratio of about 110% to about 800%. -
Coating ratio=[(W f −W 0)/W 0]×100(%) [Equation 1] -
- (W0: weight (g) of highly crystalline carbon in the substrate, and
- Wf: weight (g) of total polymerization product including the substrate and a crystalline carbon layer)
- When the coating ratio of carbon layer is within this range, the carbon layer may be uniformly coated on the substrate including the highly crystalline carbon, and the highly crystalline graphitic layer structure may be easily formed without deteriorating the characteristics of high crystalline carbon.
- Then, the substrate coated with graphitizable polymer may be stabilized. The stabilizing may include a chemical reaction such as crosslinking, oxidation, aromatization, dehydrogenation, or cyclization of graphitizable polymer.
- The stabilizing may be performed with a rising temperature at a heat-up rate of about 3° C./min to about 5° C./min under the air atmosphere to a final temperature of about 220° C. to about 280° C. and then continuing at the final temperature for about 30 minutes to about 2 hours.
- According to the stabilizing process, the graphitizable polymer may adsorb oxygen from the air as part of the cycling and the crosslinking linkage, so as to provide a thermally stable ladder polymer structure in the following carbonizing process according to the reaction. If the temperature of the stabilizing process is lower than the range, the reaction may occur too slowly, and the stabilization may be incompletely performed, so as to deteriorate the carbon physical properties. On the other hand, if the temperature of the stabilization process is higher than the range, the graphitizable polymer may be excessively heated to be melted or combusted, which is unfavorable.
- Then, the stabilized substrate may be subjected to a first heat-treating process. The first heat-treating process may be performed under a N2 or Ar atmosphere at a heat-up rate of about 3° C./min to about 5° C./min and maintained at about 300° C. to about 700° C. for about 30 minutes to about 6 hours. According to the first heat-treating process, the carbon content may be increased to be greater than or equal to about 90 wt % by exhausting various gases, or a three dimensional carbon structure having molecular and fibrillar orientation may be formed. In addition, the polymer chain maybe rearranged according to the first heat-treatment so that the parallel molecular chain may form a three dimensional bond. In addition, the effects according to the first heat-treating process may be further effectively obtained when the heat-treatment is performed under the above-mentioned conditions.
- Then, the first heat-treated substrate may be subjected to a second heat-treating process to be carbonized. According to the carbonizing process, the polymer coated on the substrate may be carbonized. The second heat-treating process includes a first step of heating at about 400° C. to about 800° C. and a second step of heating at about 800° C. to about 1200° C. When the second heat-treating process is performed in the first and the second steps within the temperature range, structures such as graphite oxide may be removed, and carbon with an sp2 structure may be developed.
- The substrate that has undergone the carbonizing process may be subjected to a third heat-treating process to be graphitized. According to the graphitization, the carbonized polymer is finally graphitized to provide graphite, which is a crystalline carbon layer, on the substrate. The third heat-treating process may be performed by heating at about 1200° C. to about 2500° C.
- When performing a third heat-treating process, the formed graphitic layer structure may be further developed and arranged, and graphene sheets may be stacked together well. Accordingly, a uniform graphitic layer may be provided that may slow the kinetics of carbon oxidation to improve the anti-corrosion properties of carbon. The high temperature graphitization process may remove an amorphous phase to enhance the graphitized structure arrangement, so that a mesoporous channel aligned with graphene layers may be well developed.
- When third heat-treatment is performed within the temperature range, the effects of the third heat-treatment may be more effectively obtained, and mesopore channels aligned together with the arranged graphitized structure may be more readily formed and may be well developed.
- Another embodiment provides a catalyst for a fuel cell including the support and an active metal supported on the support.
- The active metal may be platinum, ruthenium, osmium, a platinum-ruthenium alloy, a platinum-osmium alloy, a platinum-palladium alloy, a platinum-M alloy (M is at least one transition element selected from Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sn, Mo, W, Rh, and Ru), or a combination thereof. The catalyst according to one embodiment may be used in an anode and/or a cathode. The anode and cathode may include the same catalyst. In an implementation, a direct oxidation fuel cell may include a platinum-ruthenium alloy catalyst as an anode catalyst in order to prevent catalyst poisoning in the anode reaction. Specific examples of the catalyst may include one selected from Pt, Pt/Ru, Pt/W, Pt/Ni, Pt/Sn, Pt/Mo, Pt/Pd, Pt/Fe, Pt/Cr, Pt/Co, Pt/Ru/W, Pt/Ru/Mo, Pt/Ru/V, Pt/Fe/Co, Pt/Ru/Rh/Ni, and Pt/Ru/Sn/W.
- The process of supporting the active metal in a support may be carried out by any suitable process.
- Yet another embodiment provides an electrode for a fuel cell including a catalyst layer including the catalyst and an electrode substrate.
- The catalyst layer may further include a binder resin to improve its adherence and proton transfer properties.
- The binder resin may be a proton conductive polymer resin. Examples of the binder resin may include a polymer resin having a cation exchange group selected from a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, a phosphonic acid group, and derivatives thereof at its side chain. Examples of the polymer resin may include at least one proton conductive polymer selected from a fluoro-based polymer, a benzimidazole-based polymer, a polyimide-based polymer, a polyetherimide-based polymer, a polyphenylenesulfide-based polymer, a polysulfone-based polymer, a polyethersulfone-based polymer, a polyetherketone-based polymer, a polyether-etherketone-based polymer, and a polyphenylquinoxaline-based polymer.
- The hydrogen (H) in the cation exchange group of the proton conductive polymer may be substituted with Na, K, Li, Cs, or tetrabutylammonium. When the H in the cation exchange group of the terminal end of the proton conductive polymer side chain is substituted with Na or tetrabutylammonium, NaOH or tetrabutylammonium hydroxide may be used during preparation of the catalyst composition, respectively. When the H is substituted with K, Li, or Cs, suitable compounds for the substitutions may be used.
- The binder resin may be used singularly or in combination. The binder resin may be used along with non-conductive polymers to improve adherence with a polymer electrolyte membrane. The binder resin may be used in a controlled amount.
- Examples of the non-conductive polymers include at least one selected from polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkylvinylether copolymer (PFA), ethylene/tetrafluoroethylene (ETFE), ethylenechlorotrifluoro-ethylene copolymer (ECTFE), polyvinylidenefluoride, a polyvinylidenefluoride-hexafluoropropylene copolymer (PVdF-HFP), dodecylbenzenesulfonic acid, and sorbitol.
- The electrode substrate plays a role of supporting an electrode and diffusing a fuel and an oxidant into a catalyst layer, so that the fuel and the oxidant may easily approach the catalyst layer. The electrode substrates may be formed from a material such as carbon paper, carbon cloth, carbon felt, or a metal cloth (a porous film composed of metal fiber or a metal film disposed on a surface of a cloth composed of polymer fibers), as examples.
- The electrode substrates may be treated with a fluorine-based resin to be water-repellent to prevent deterioration of diffusion efficiency due to water generated during operation of a fuel cell. The fluorine-based resin may be one selected from polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, polyperfluoroalkylvinylether, polyperfluorosulfonylfluoride alkoxyvinyl ether, fluorinated ethylene propylene, polychlorotrifluoroethylene, and a copolymer thereof.
- In order to increase reactant diffusion effects between the electrode substrates and catalyst layer, the anode or cathode may further include a microporous layer on an electrode substrate. The microporous layer may include conductive powders with a certain particle diameter. The conductive material may include, but is not limited to, carbon powder, carbon black, acetylene black, activated carbon, a carbon fiber, fullerene, carbon nanotubes, carbon nanowires, carbon nanohorns, carbon nanorings, or combinations thereof.
- The microporous layer is formed by coating a composition including a conductive powder, a binder resin, and a solvent on the conductive substrate. The binder resin may include, for example, polytetrafluoroethylene, polyvinylidenefluoride, polyhexafluoropropylene, polyperfluoroalkylvinylether, polyperfluorosulfonylfluoride, alkoxyvinyl ether, polyvinylalcohol, cellulose acetate, or a copolymer thereof. The solvent may include, for example, an alcohol such as ethanol, isopropyl alcohol, n-propyl alcohol, butanol, etc., water, dimethyl acetamide, dimethyl sulfoxide, N-methylpyrrolidone, or tetrahydrofuran. The coating method may include, for example, screen printing, spray coating, doctor blade methods, gravure coating, dip coating, silk screening, painting, etc., depending on the viscosity of the composition.
- According to another embodiment, a membrane-electrode assembly for a fuel cell including the electrode as either one of a cathode or an anode is provided. The membrane-electrode assembly for a fuel cell includes a cathode and an anode facing each other, and a polymer electrolyte membrane interposed between the cathode and anode.
- The polymer electrolyte membrane may be any generally-used polymer electrolyte membrane made of a proton conductive polymer resin. The proton conductive polymer resin may be a polymer resin having a cation exchange group selected from a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, a phosphonic acid group, and derivatives thereof, at its side chain.
- Examples of the polymer resin include at least one selected from a fluoro-based polymer, a benzimidazole-based polymer, a polyimide-based polymer, a polyetherimide-based polymer, a polyphenylenesulfide-based polymer, a polysulfone-based polymer, a polyethersulfone-based polymer, a polyetherketone-based polymer, a polyether-etherketone-based polymer, and a polyphenylquinoxaline-based polymer. According to implementations, the polymer resin may include poly(perfluorosulfonic acid) (commercially available as “NAFION”), poly(perfluorocarboxylic acid), a copolymer of tetrafluoroethylene having a sulfonic acid group and fluorovinylether, defluorinated polyetherketone sulfide, an aryl ketone, or poly[(2,2′-m-phenylene)-5,5′-bibenzimidazole].
- The hydrogen (H) in the cation exchange group of the proton conductive polymer may be substituted with Na, K, Li, Cs, or tetrabutylammonium. When the H in the cation exchange group of the terminal end of the proton conductive polymer side chain is substituted with Na or tetrabutylammonium, NaOH or tetrabutylammonium hydroxide may be used during preparation of the catalyst composition, respectively. When the H is substituted with K, Li, or Cs, suitable compounds for the substitutions may be used. Such a Na, K, Li, Cs, or tetrabutylammonium may be converted into a proton during a subsequent acid treatment of a catalyst layer, and thus, a proton form (H+-form) polymer electrolyte membrane may be provided.
- Another embodiment provides a fuel cell system including at least one electricity generating element, a fuel supplier, and an oxidant supplier.
- The electricity generating element may include the membrane-electrode assembly according to one embodiment and a separator (referred to as a bipolar plate). The electricity generating element may generate electricity through oxidation of a fuel and reduction of an oxidant.
- The fuel supplier may supply the electricity generating element with a fuel, while the oxidizing agent supplier may supply the electricity generating element with an oxidizing agent such as oxygen or air.
- In an implementation, the fuel may include liquid or gaseous hydrogen or a hydrocarbon fuel. The hydrocarbon fuel, for example, may be methanol, ethanol, propanol, butanol, or natural gas.
-
FIG. 1 illustrates the schematic structure of a fuel cell system according to an embodiment, which will be described in details with the reference to this accompanying drawing as follows. AlthoughFIG. 1 shows a fuel cell system supplying a fuel and an oxidizing agent to an electrical generating element using a pump, in other implementations, the fuel cell system of the embodiment may include a structure wherein a fuel and an oxidant are provided by diffusion. - A
fuel system 1 of the embodiment may include at least oneelectricity generating element 3 that generates an electrical energy by oxidation of a fuel and reduction of an oxidizing agent, afuel supplier 5 that supplies the fuel, and anoxidant supplier 7 that supplies an oxidant to theelectricity generating element 3. - In addition, the
fuel supplier 5 may be equipped with atank 9, which stores fuel, and apump 11, which is connected therewith. Thefuel pump 11 may supply fuel stored in thetank 9 with a predetermined pumping power. - The
oxidant supplier 7, which supplies theelectricity generating element 3 with an oxidant, may be equipped with at least oneoxidant pump 13 for supplying an oxidant with a predetermined pumping power. - The
electricity generating element 3 may include a membrane-electrode assembly 17, which oxidizes hydrogen or a fuel and reduces an oxidant, andseparators stack 15 may be provided by stacking at least one of theelectricity generating elements 3. - The following Examples and Comparative Examples are provided in order to highlight characteristics of one or more embodiments, but it will be understood that the Examples and Comparative Examples are not to be construed as limiting the scope of the embodiments, nor are the Comparative Examples to be construed as being outside the scope of the embodiments. Further, it will be understood that the embodiments are not limited to the particular details described in the Examples and Comparative Examples.
- 2.0 g of a highly crystalline carbon in the form of carbon nanotube was treated with an ultrasonic wave in 20 ml of deionized water for 20 minutes to provide a carbon suspension. 33 ml of acrylonitrile was added to the carbon suspension and agitated for 30 minutes. 1.08 g of ammonium persulfate ((NH4)2S2O8) was added thereto, and agitated under the nitrogen atmosphere at 65° C. for 24 hours to provide emulsion polymerization.
- After the polymerization, the polymerized product was centrifuged and washed with deionized water and ethanol. Then, the washed product was vacuum-dried at 60° C. to provide a carbon substrate coated with polyacrylonitile (PAN) layer as a support precursor.
- A support precursor, in the form of a carbon substrate coated with a polyacrylonitrile layer, was prepared in accordance with the same procedure as in Preparation Example 1, except that after the 1.08 g of ammonium persulfate ((NH4)2S2O8) was added, the agitating under the nitrogen atmosphere at 65° C. was carried out for 1 hour to provide the emulsion polymerization.
- A support precursor, a carbon substrate coated with a polyacrylonitrile layer, was prepared in accordance with the same procedure as in Preparation Example 1, except that after the 1.08 g of ammonium persulfate ((NH4)2S2O8) was added, the agitating under the nitrogen atmosphere at 65° C. was carried out for 2 hours to provide the emulsion polymerization.
- A support precursor, a carbon substrate coated with a polyacrylonitrile layer, was prepared in accordance with the same procedure as in Preparation Example 1, except that after the 1.08 g of ammonium persulfate ((NH4)2S2O8) was added, the agitating under the nitrogen atmosphere at 65° C. was carried out for 6 hours to provide the emulsion polymerization.
- A support precursor, a carbon substrate coated with a polyacrylonitrile layer, was prepared in accordance with the same procedure as in Preparation Example 1, except that after 1.08 g of ammonium persulfate ((NH4)2S2O8) was added, the agitating under the nitrogen atmosphere at 65° C. was carried out for 12 hours to provide the emulsion polymerization.
- The coating ratio of polyacrylonitrile layer (carbon layer) of each support precursors obtained from the Preparation Examples 1 to 5 was calculated, and the results are shown in the following Table 1.
-
Polymerization Coating time (hour) ratio (%) Preparation Example 1 24 790 Preparation Example 2 1 135 Preparation Example 3 2 195 Preparation Example 6 420 Preparation Example 5 12 680 - The carbon substrate formed with the PAN coating layer obtained from Preparation Example 1 was stabilized at a heat-up rate of 3° C./min at 280° C. for 1 hour to provide a carbon support coated with a PAN layer.
- The carbon substrate formed with the PAN coating layer obtained from Preparation Example 1 was stabilized at a heat-up rate of 3° C./min at 280° C. for 1 hour and subjected to a first heat-treatment under a N2 atmosphere at a heat-up rate of 3° C./min at 400° C. for 2 hours. Then, the first heat-treated product was subjected to a second heat-treatment to provide a carbon support coated with a PAN layer. The second heat-treatment was performed with a first step of heating at 450° C. and second step of heating at 800° C.
- The carbon substrate formed with a PAN coating layer obtained Preparation Example 1 was stabilized at 280° C. for 1 hour with a heat-up rate of 3° C./min, and the obtained product subjected to a first heat-treatment at a heat-up rate of 3° C./min under an N2 atmosphere at 400° C. for 2 hours, and the first-treated product was subjected to a second heat-treatment. The second heat-treatment was performed with a first step of heating at 450° C. and a second step of heating at 800° C. Then the second heat-treated product was subjected to a third heat-treatment at 2000° C. to provide a carbon support coated with a crystalline carbon layer.
FIG. 2 is a TEM photograph of the obtained carbon support coated with a crystalline carbon layer, from which it may be determined that the crystalline carbon layer had a thickness of about 15 nm. The crystalline carbon has an interlayer spacing (d002) of a (002) plane of 3.4 Å. - A carbon support coated with the crystalline carbon layer was fabricated in accordance with the same procedure as in Example 1, except that the third heat-treatment was performed at 2500° C.
- A carbon support coated with a PAN layer was fabricated in accordance with the same procedure as in Comparative Example 2, except that the second step of heating during the second heat-treatment was performed at 1000° C.
- The support precursor obtained from Preparation Example 1 was analyzed by FT-IR, and the results are shown in
FIG. 3 . As shown inFIG. 3 , the support precursor obtained from Preparation Example 1 showed a strong peak corresponding to the stretching vibration of a CN group around 2240 cm−1. Thereby, it may be determined that the polyacrylonitrile (PAN) chain was formed on the crystalline carbon surface according to the chemical polymerization. - XPS Analysis
- The support obtained from the Comparative Example 1 and the support precursor obtained from Preparation Example 1 were analyzed by X-ray photoelectron spectroscopy (XPS), and the results are shown in
FIG. 4 . As shown inFIG. 4 , in addition to a C1s (about 285 eV) signal and an O1s (about 532 eV) signal, a N1s (about 399 eV) signal was also observed. From the results, it may be determined that the PAN coating layer introduced by the chemical polymerization was formed on the surface of crystalline carbon. - A Pt nanoparticle was supported on the support obtained from Example 2 to provide a catalyst. The catalyst was imaged by HR (high resolution)-TEM, and the results are shown in
FIG. 5 . From the results shown inFIG. 5 , it may be seen that the Pt nano particles were uniformly supported on the support. In addition,FIG. 6 shows an HR-TEM image of the support obtained from Example 2. As shown inFIG. 6 , it may be seen that the obtained support had a structure of a substrate and a crystalline carbon layer disposed on the substrate. - A catalyst for a fuel cell was fabricated by supporting Pt on the support obtained from Comparative Example 1 according to the chemical reduction.
- A catalyst for a fuel cell was fabricated by supporting Pt on the support obtained from Comparative Example 2 according to the chemical reduction.
- A catalyst for a fuel cell was fabricated by supporting Pt on the support obtained from Example 1 according to the chemical reduction.
- A catalyst for a fuel cell was fabricated by supporting Pt on the support obtained from Example 2 according to the chemical reduction.
- A catalyst (Pt/CNT) for a fuel cell was fabricated by supporting Pt on a carbon nanotube support formed with no carbon layer according to the chemical reduction.
- The carbon support obtained from Example 1 was analyzed by high resolution XPS C1s core-level spectroscopy, and the results are shown in (a) of
FIG. 7 . In addition, the catalyst obtained from Example 3 was measured by high resolution XPS Pt4f core-level spectroscopy, and the results are shown in (b) ofFIG. 7 . As shown in (a) and (b) ofFIG. 7 , it may be determined that, in the catalyst obtained from Example 3, Pt nanoparticle was uniformly supported on the support including a high crystalline carbon graphitized layer. - Electrochemical Characteristic Evaluation
- 0.25 mg/
cm 2 of each catalyst obtained from Examples 3, 4 and Comparative Examples 4 to 6 was added to a solvent including water mixed with dipropylene glycol at a weight ratio of 50:50. An ionomer of 5 wt % Nafion (Dupont) was added to provide a catalyst composition for an electrode. The ionomer was included in an amount of 40 wt % based on the total amount of the ionomer and catalyst. The catalyst composition was coated onto a glassy carbon electrode to provide a half-cell electrode for cyclic voltammetry (CV). Cyclic voltammetry (CV) was carried out with respect to the half-cell, and the decreasing rate of an electrochemical active surface area (ECSA) was measured. The decreasing ratio of the electrochemical active surface area after carrying out the CV compared to the initial electrochemical active surface area before carrying out the CV was calculated in terms of a percentage (%), and the results are shown inFIG. 8 . The CV test was performed by using a potentiostat (VSP, Bio-Logic SA), and a rotation control (Pine) in a setup of a temperature controller standard three-compartment electrode. In this case, a Pt-mesh electrode and an Ag/AgCl electrode were used as a counter electrode and a reference electrode, respectively. The electrochemical active surface area was calculated as the average of the peak area of hydrogen adsorption and desorption excepting the double layer charge values. Using an N2-saturated 0.1M HClO4 solution, cycles were repeated at 0.6V to 1.4V for 1000 times, and ECSA was measured in each 100 cycles at a scan rate of 20 mW/s. - As shown in
FIG. 8 , the decreasing ratio of electrochemical active surface area of Examples 3 and 4 was less than that of Comparative Examples 4 to 6. Particularly, it may be determined that, in the case of Example 4, the electrochemical active surface area barely decreased. - In addition, the half-cell was measured with respect to electrochemical surface area, and the results are shown in
FIG. 9 . As shown inFIG. 9 , it may be determined that the catalysts of Examples 3 and 4 had a significantly smaller decreasing ratio of electrochemical surface area than the catalysts of Comparative Examples 4 to 6. Particularly, it may be determined that the electrochemical surface area was barely decreased even after the 1000th cycle in Example 4. Accordingly, it may be estimated that the catalysts of Examples 3 and 4 had superior electrochemical stability and durability to those of Comparative Examples 4 to 6. - Measuring Raman Spectrum
- The supports obtained from Examples 1 and 2 and Comparative Examples 1 and 2 were analyzed by Raman spectroscopy, and the results are shown in
FIG. 10 . For the comparison, the catalyst according to Comparative Example 6 and a Control including only CNT were measured for Raman spectrum, and the results are also shown inFIG. 10 . As shown inFIG. 10 , the similar results are shown in all of Examples 1 and 2 and Comparative Examples 1, 2, 6, and CNT, so it may be determined that the support according to Examples 1 and 2 maintained a similar structure to those of the conventional supports. - Measuring Raman Spectrum Intensity Ratio
- The supports of Examples 1 and 2 to Comparative Examples 1 and 2, and, for the comparison, the catalyst obtained from Comparative Example 6 and the Control of CNT were measured to determine a Raman spectrum area ratio (area integral ratio) and an intensity ratio at a (1580 cm−1) plane and (1360 cm−1) plane. From these measurements, the ID/IG area ratio (area (1360 cm−1)/area (1580 cm−1)) and the ID/IG intensity ratio (intensity (1360 cm−1)/intensity (1580 cm−1)) were calculated. The results are shown in
FIG. 11 . From the results shown inFIG. 11 , it may be confirmed that the catalyst of Comparative Example 6 had a ID/IG area ratio of about 0.91, a ID/IG intensity ratio of about 0.69; and the catalysts of Control and Comparative Examples 1 and 2 had a ID/IG area ratio of about 0.78 to about 0.93, a ID/IG intensity ratio of about 0.53 to about 0.65. On the other hand, the catalysts of Examples 1 to 2 had a ID/IG area ratio of about 0.35, a ID/IG intensity ratio of about 0.24. According to the results, the supports according to Examples 1 to 2 had a different Raman spectrum area ratio and intensity ratio from those of Comparative Examples 1, 2, 6 and the Control. In addition, it may be determined that the supports according to Examples 1 to 2 had a ID/IG area ratio of about 38%, a ID/IG intensity ratio of about 35% relative to the catalyst according to Comparative Example 6. - By way of summation and review, embodiments provide a support for a fuel cell being capable of improving catalyst activity. Embodiments provide a method of preparing the support for a fuel cell. Embodiments provide an electrode for a fuel cell including the support for a fuel cell. Embodiments provide a membrane-electrode assembly for a fuel cell including the electrode. Embodiments provide a fuel cell system including the membrane-electrode assembly.
- Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope thereof as set forth in the following claims.
Claims (6)
1. A method of preparing the support for a fuel cell, the method comprising:
adding a monomer for a graphitizable polymer to a liquid containing a highly crystalline carbon suspended therein to prepare a mixture, the highly crystalline carbon having a Raman spectrum intensity ratio between a (1360) plane and a (1580) plane, ID/IG ((I(1360 cm−1)/I(1580 cm−1)) of about 0.24 to about 0.91;
adding a polymerization initiator to the mixture to perform polymerization and prepare a polymerization product;
stabilizing the polymerization product to prepare a stabilized product;
first heat-treating the stabilized product to provide a first heat-treated product;
second heat-treating and carbonizing the first heat-treated product to provide a resultant; and
third heat-treating and graphitizing the resultant.
2. The method of preparing the support for a fuel cell as claimed in claim 1 , wherein the polymerization product includes highly crystalline carbon and a carbon layer in a form of a continuous coating on the highly crystalline carbon, wherein the carbon layer has a coating ratio represented by the following Equation 1 of about 100% to about 800%:
Coating ratio=[(W f −W 0)/W 0]×100(%) [Equation 1]
Coating ratio=[(W f −W 0)/W 0]×100(%) [Equation 1]
wherein, W0 denotes a weight (g) of highly crystalline carbon in the substrate, and
Wf denotes a weight (g) of total polymerization product in the substrate and carbon layer.
3. The method of preparing the support for a fuel cell as claimed in claim 1 , wherein the first heat-treating is performed at about 300° C. to about 700° C.
4. The method of preparing the support for a fuel cell as claimed in claim 1 , wherein the stabilizing is performed at about 220° C. to about 280° C.
5. The method of preparing the support for a fuel cell as claimed in claim 1 , wherein the second heat-treating includes a first heating stage at about 400° C. to about 800° C., and second heating stage at about 800° C. to about 1200° C.
6. The method of preparing the support for a fuel cell as claimed in claim 1 , wherein the third heat-treating is performed at about 1200° C. to about 2500° C.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US17/088,732 US20210057761A1 (en) | 2013-03-04 | 2020-11-04 | Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR10-2013-0022990 | 2013-03-04 | ||
KR1020130022990A KR101995830B1 (en) | 2013-03-04 | 2013-03-04 | Supporter for fuel cell, method of preparing same, and electrode for fuel cell, membrane-electrode assembly for a fuel cell and fuel cell system including same |
US14/069,853 US10862136B2 (en) | 2013-03-04 | 2013-11-01 | Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same |
US17/088,732 US20210057761A1 (en) | 2013-03-04 | 2020-11-04 | Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/069,853 Division US10862136B2 (en) | 2013-03-04 | 2013-11-01 | Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same |
Publications (1)
Publication Number | Publication Date |
---|---|
US20210057761A1 true US20210057761A1 (en) | 2021-02-25 |
Family
ID=51421086
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/069,853 Active 2035-10-24 US10862136B2 (en) | 2013-03-04 | 2013-11-01 | Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same |
US17/088,732 Pending US20210057761A1 (en) | 2013-03-04 | 2020-11-04 | Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/069,853 Active 2035-10-24 US10862136B2 (en) | 2013-03-04 | 2013-11-01 | Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same |
Country Status (2)
Country | Link |
---|---|
US (2) | US10862136B2 (en) |
KR (1) | KR101995830B1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20180036107A (en) * | 2016-09-30 | 2018-04-09 | 코오롱인더스트리 주식회사 | Support, electrode for fuel cell, and membrane-electrode assembly, and fuel cell comprising the same |
CN106549166A (en) * | 2016-12-07 | 2017-03-29 | 黄河科技学院 | The carrier and its preparation method of the electrode catalyst of one proton exchanging film fuel battery |
KR102212692B1 (en) * | 2019-02-19 | 2021-02-04 | 인하대학교 산학협력단 | Electrochemical catalyst for oxygen reduction reaction using carbon black and method for producing the same |
KR20220091754A (en) | 2020-12-24 | 2022-07-01 | 현대자동차주식회사 | Intermetallic catalyst and method for preparing the same |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120231338A1 (en) * | 2009-12-07 | 2012-09-13 | National University Corporation Gunma University | Support for catalyst supporting, carrier with supported catalyst, electrode, and battery |
US20140225041A1 (en) * | 2011-06-30 | 2014-08-14 | Cornell University | Hybrid Materials and Nanocomposite Materials, Methods of Making Same, and Uses Thereof |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4266624B2 (en) * | 2002-12-02 | 2009-05-20 | 三洋電機株式会社 | Fuel cell electrode and fuel cell |
US7956108B2 (en) * | 2003-05-30 | 2011-06-07 | The Provost, Fellows And Scholars Of The College Of The Holy And Undivided Trinity Of Queen Elizabeth, Near Dublin | Product |
JP2007535787A (en) | 2004-03-15 | 2007-12-06 | キャボット コーポレイション | Modified carbon products, use of modified carbon products in fuel cells and similar devices, and methods relating to modified carbon products |
JP2006008472A (en) * | 2004-06-29 | 2006-01-12 | Hitachi Powdered Metals Co Ltd | Nano-structured graphite, its composite material, conductive material and catalyst material using them |
US7842432B2 (en) * | 2004-12-09 | 2010-11-30 | Nanosys, Inc. | Nanowire structures comprising carbon |
KR100763548B1 (en) * | 2006-01-16 | 2007-10-04 | 주식회사 아모메디 | preparation method of diffusion layer of fuel cell |
JP2009226318A (en) | 2008-03-24 | 2009-10-08 | Fujifilm Corp | Platinum-supported carbon, catalyst for fuel cell, electrode membrane cemented product and fuel cell |
JP5328290B2 (en) * | 2008-10-22 | 2013-10-30 | トヨタ自動車株式会社 | Fuel cell electrode catalyst |
KR20110070353A (en) | 2009-12-18 | 2011-06-24 | 한국생산기술연구원 | Non-platinum cathode catalyst for polymer electrolyte membrane fuel cell and electrode manufacturing by cathode catalyst and membrane electrode assembly manufacturing by electrode |
-
2013
- 2013-03-04 KR KR1020130022990A patent/KR101995830B1/en active IP Right Grant
- 2013-11-01 US US14/069,853 patent/US10862136B2/en active Active
-
2020
- 2020-11-04 US US17/088,732 patent/US20210057761A1/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120231338A1 (en) * | 2009-12-07 | 2012-09-13 | National University Corporation Gunma University | Support for catalyst supporting, carrier with supported catalyst, electrode, and battery |
US20140225041A1 (en) * | 2011-06-30 | 2014-08-14 | Cornell University | Hybrid Materials and Nanocomposite Materials, Methods of Making Same, and Uses Thereof |
Also Published As
Publication number | Publication date |
---|---|
US20140248552A1 (en) | 2014-09-04 |
US10862136B2 (en) | 2020-12-08 |
KR101995830B1 (en) | 2019-07-03 |
KR20140108977A (en) | 2014-09-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20210057761A1 (en) | Support for fuel cell, method of preparing the same, and electrode for fuel cell, membrane-electrode assemby for a fuel cell and fuel cell system including same | |
US8637208B2 (en) | Electrode for fuel cell, membrane-electrode assembly including same, and fuel cell system including same | |
US8007957B2 (en) | Electrode for fuel cell, fuel cell system comprising the same, and method for preparing the same | |
US20070099069A1 (en) | Catalyst for a fuel cell, a method for preparing the same, and a membrane-electrode assembly for a fuel cell including the same | |
US7887972B2 (en) | Cathode catalyst for fuel cell, method of preparing same, and membrane-electrode assembly and fuel cell comprising same | |
US20180123140A1 (en) | N-doped carbon nanomaterials as catalysts for oxygen reduction reaction in acidic fuel cells | |
JP4585492B2 (en) | Fuel cell electrode, membrane-electrode assembly including the same, and fuel cell system including the same | |
US9343750B2 (en) | Supporter for fuel cell, and electrode for fuel cell, membrane-electrode assembly for a fuel cell, and fuel cell system including same | |
US9543590B2 (en) | Catalyst layer composition for fuel cell, electrode for fuel cell, method of preparing electrode for fuel cell, membrane-electrode assembly for fuel cell, and fuel cell system using the membrane-electrode assembly | |
US8685594B2 (en) | Catalyst for cathode of fuel cell, and membrane-electrode assembly for fuel cell | |
KR20110078573A (en) | Fuel cell electrode and method of fabricating thereof | |
US9012107B2 (en) | Cathode catalyst for fuel cell, method of preparing same, and membrane-electrode assembly comprising same | |
EP2031685A1 (en) | Cathode Catalyst, Method for Preparing the Same, Membrane-Electrode Assembly and Fuel Cell System Including the Same | |
US20100330453A1 (en) | Polymer electrolyte membrane for fuel cell system and manufacturing method thereof | |
KR20180088050A (en) | Catalyst composition of fuel cell, catalyst layer manufactured by the same and fuel cell comprising the same | |
US8846272B2 (en) | Anode for fuel cell, membrane-electrode assembly for fuel cell including same, and fuel cell system including same | |
EP1811595A1 (en) | Cathode catalyst, membrane-electrode assembly and fuel cell system | |
KR102187990B1 (en) | Manufacturing method of catalyst ink for forming fuel cell electrode catalyst layer | |
KR20120087402A (en) | Carboaceous nanomaterail and method of preparing the same | |
KR20070076284A (en) | Cathode catalyst for fuel cell, the method of preparing same, membrane-electrode assembly for fuel cell comprising same and fuel cell system comprising same | |
KR20140045808A (en) | Catalyst for fuel cell, electrode for fuel cell including same, membrane-electrode assembly and fuel cell system including same and fuel cell system including same | |
KR20120087403A (en) | Cathode for fuel cell, membrane-electrode assembly and fuel cell system including same | |
US8039172B2 (en) | Cathode catalyst for a fuel cell, and a membrane-electrode assembly for a fuel cell and a fuel cell system comprising the same | |
KR100684803B1 (en) | Method of preparing cathode catalyst for fuel cell, cathode electrode for fuel cell and fuel cell system comprising cathode catalyst prepared by the method | |
KR20080023915A (en) | Electrode for fuel cell and membrane-electrode assembly for fuel cell system comprising same |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STPP | Information on status: patent application and granting procedure in general |
Free format text: APPLICATION DISPATCHED FROM PREEXAM, NOT YET DOCKETED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |