KR20240001408A - Catalyst for fuel cell containing transition metal, manufacturing method thereof, and fuel cell comprising same - Google Patents
Catalyst for fuel cell containing transition metal, manufacturing method thereof, and fuel cell comprising same Download PDFInfo
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- KR20240001408A KR20240001408A KR1020220078007A KR20220078007A KR20240001408A KR 20240001408 A KR20240001408 A KR 20240001408A KR 1020220078007 A KR1020220078007 A KR 1020220078007A KR 20220078007 A KR20220078007 A KR 20220078007A KR 20240001408 A KR20240001408 A KR 20240001408A
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- catalyst
- alloy particles
- carbon
- fuel cells
- fuel cell
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- 239000003054 catalyst Substances 0.000 title claims abstract description 96
- 239000000446 fuel Substances 0.000 title claims abstract description 53
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 21
- 229910052723 transition metal Inorganic materials 0.000 title claims abstract description 19
- 150000003624 transition metals Chemical class 0.000 title claims abstract description 17
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 76
- 239000002245 particle Substances 0.000 claims abstract description 41
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 36
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 36
- 239000000956 alloy Substances 0.000 claims abstract description 36
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 24
- 238000000034 method Methods 0.000 claims abstract description 9
- 239000002243 precursor Substances 0.000 claims description 20
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical group [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- 229910052697 platinum Inorganic materials 0.000 claims description 15
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 12
- 239000002253 acid Substances 0.000 claims description 11
- 239000006185 dispersion Substances 0.000 claims description 9
- 239000003638 chemical reducing agent Substances 0.000 claims description 8
- 229910052759 nickel Inorganic materials 0.000 claims description 8
- 239000003960 organic solvent Substances 0.000 claims description 7
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 6
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 6
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 claims description 6
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 claims description 6
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 5
- 229910021591 Copper(I) chloride Inorganic materials 0.000 claims description 4
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 4
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 claims description 4
- 101150003085 Pdcl gene Proteins 0.000 claims description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 4
- 229910052804 chromium Inorganic materials 0.000 claims description 4
- 229910052802 copper Inorganic materials 0.000 claims description 4
- OXBLHERUFWYNTN-UHFFFAOYSA-M copper(I) chloride Chemical compound [Cu]Cl OXBLHERUFWYNTN-UHFFFAOYSA-M 0.000 claims description 4
- 238000001035 drying Methods 0.000 claims description 4
- 229910052741 iridium Inorganic materials 0.000 claims description 4
- 229910052742 iron Inorganic materials 0.000 claims description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical class C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims description 4
- 229910052763 palladium Inorganic materials 0.000 claims description 4
- CLSUSRZJUQMOHH-UHFFFAOYSA-L platinum dichloride Chemical group Cl[Pt]Cl CLSUSRZJUQMOHH-UHFFFAOYSA-L 0.000 claims description 4
- 229910052707 ruthenium Inorganic materials 0.000 claims description 4
- 239000011734 sodium Substances 0.000 claims description 4
- 229910052718 tin Inorganic materials 0.000 claims description 4
- 229910052721 tungsten Inorganic materials 0.000 claims description 4
- 229910052720 vanadium Inorganic materials 0.000 claims description 4
- NWZSZGALRFJKBT-KNIFDHDWSA-N (2s)-2,6-diaminohexanoic acid;(2s)-2-hydroxybutanedioic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O.NCCCC[C@H](N)C(O)=O NWZSZGALRFJKBT-KNIFDHDWSA-N 0.000 claims description 3
- 239000006229 carbon black Substances 0.000 claims description 3
- 239000002041 carbon nanotube Substances 0.000 claims description 3
- 229910021393 carbon nanotube Inorganic materials 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- IKDUDTNKRLTJSI-UHFFFAOYSA-N hydrazine monohydrate Substances O.NN IKDUDTNKRLTJSI-UHFFFAOYSA-N 0.000 claims description 3
- 239000003273 ketjen black Substances 0.000 claims description 3
- 239000000843 powder Substances 0.000 claims description 3
- 239000012279 sodium borohydride Substances 0.000 claims description 3
- 229910000033 sodium borohydride Inorganic materials 0.000 claims description 3
- 238000005406 washing Methods 0.000 claims description 3
- 229910021589 Copper(I) bromide Inorganic materials 0.000 claims description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 2
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 2
- UWHCKJMYHZGTIT-UHFFFAOYSA-N Tetraethylene glycol, Natural products OCCOCCOCCOCCO UWHCKJMYHZGTIT-UHFFFAOYSA-N 0.000 claims description 2
- 239000006230 acetylene black Substances 0.000 claims description 2
- CDQSJQSWAWPGKG-UHFFFAOYSA-N butane-1,1-diol Chemical compound CCCC(O)O CDQSJQSWAWPGKG-UHFFFAOYSA-N 0.000 claims description 2
- 239000002134 carbon nanofiber Substances 0.000 claims description 2
- SZXQTJUDPRGNJN-UHFFFAOYSA-N dipropylene glycol Chemical compound OCCCOCCCO SZXQTJUDPRGNJN-UHFFFAOYSA-N 0.000 claims description 2
- 239000002063 nanoring Substances 0.000 claims description 2
- 239000002070 nanowire Substances 0.000 claims description 2
- 229910017604 nitric acid Inorganic materials 0.000 claims description 2
- 235000006408 oxalic acid Nutrition 0.000 claims description 2
- 229910052700 potassium Inorganic materials 0.000 claims description 2
- 239000011591 potassium Substances 0.000 claims description 2
- ULWHHBHJGPPBCO-UHFFFAOYSA-N propane-1,1-diol Chemical compound CCC(O)O ULWHHBHJGPPBCO-UHFFFAOYSA-N 0.000 claims description 2
- 229910052708 sodium Inorganic materials 0.000 claims description 2
- ZIBGPFATKBEMQZ-UHFFFAOYSA-N triethylene glycol Chemical compound OCCOCCOCCO ZIBGPFATKBEMQZ-UHFFFAOYSA-N 0.000 claims description 2
- 150000001875 compounds Chemical class 0.000 claims 1
- 239000011796 hollow space material Substances 0.000 claims 1
- 229910052751 metal Inorganic materials 0.000 claims 1
- 239000002184 metal Substances 0.000 claims 1
- 239000001301 oxygen Substances 0.000 abstract description 20
- 229910052760 oxygen Inorganic materials 0.000 abstract description 20
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 19
- 238000006243 chemical reaction Methods 0.000 abstract description 15
- 238000001179 sorption measurement Methods 0.000 abstract description 14
- 239000000376 reactant Substances 0.000 abstract description 5
- 230000003111 delayed effect Effects 0.000 abstract description 3
- 229910002844 PtNi Inorganic materials 0.000 description 14
- 230000000694 effects Effects 0.000 description 13
- 230000000052 comparative effect Effects 0.000 description 8
- 238000002360 preparation method Methods 0.000 description 6
- 238000006722 reduction reaction Methods 0.000 description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 5
- 238000002441 X-ray diffraction Methods 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 description 4
- 238000005275 alloying Methods 0.000 description 4
- 238000000157 electrochemical-induced impedance spectroscopy Methods 0.000 description 4
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 3
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 3
- 229910000990 Ni alloy Inorganic materials 0.000 description 3
- 229910001260 Pt alloy Inorganic materials 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 3
- 238000000840 electrochemical analysis Methods 0.000 description 3
- 238000013507 mapping Methods 0.000 description 3
- 239000002105 nanoparticle Substances 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 238000004627 transmission electron microscopy Methods 0.000 description 3
- 230000003197 catalytic effect Effects 0.000 description 2
- 238000002484 cyclic voltammetry Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000005518 polymer electrolyte Substances 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- VZSRBBMJRBPUNF-UHFFFAOYSA-N 2-(2,3-dihydro-1H-inden-2-ylamino)-N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]pyrimidine-5-carboxamide Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)C(=O)NCCC(N1CC2=C(CC1)NN=N2)=O VZSRBBMJRBPUNF-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- NIPNSKYNPDTRPC-UHFFFAOYSA-N N-[2-oxo-2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)ethyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 NIPNSKYNPDTRPC-UHFFFAOYSA-N 0.000 description 1
- AFCARXCZXQIEQB-UHFFFAOYSA-N N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CCNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 AFCARXCZXQIEQB-UHFFFAOYSA-N 0.000 description 1
- AHVYPIQETPWLSZ-UHFFFAOYSA-N N-methyl-pyrrolidine Natural products CN1CC=CC1 AHVYPIQETPWLSZ-UHFFFAOYSA-N 0.000 description 1
- 229910002845 Pt–Ni Inorganic materials 0.000 description 1
- 238000003917 TEM image Methods 0.000 description 1
- 238000000026 X-ray photoelectron spectrum Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- QWPPOHNGKGFGJK-UHFFFAOYSA-N hypochlorous acid Chemical compound ClO QWPPOHNGKGFGJK-UHFFFAOYSA-N 0.000 description 1
- 238000005580 one pot reaction Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000010979 pH adjustment Methods 0.000 description 1
- 238000004917 polyol method Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000012916 structural analysis Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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
- H01M4/921—Alloys or mixtures with metallic elements
-
- 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
-
- 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
Abstract
본 발명은 전이금속을 포함하는 연료전지용 촉매, 이의 제조방법 및 이를 이용한 연료전지에 관한 것으로, 상기 연료전지용 촉매는 백금-전이금속 합금 입자를탄소 지지체에 담지하여 형성된 중공형 합금입자를 포함함으로써 연료전지 구동시 상용되는 Pt/C 촉매의 Pt이 반응물질인 산소와의 큰 흡착 에너지로 최종 반응까지의 반응이 늦춰지는 것을 방지하고, Pt-산소 간 흡착 에너지를 줄여 반응속도를 증가시킬 수 있다.The present invention relates to a catalyst for fuel cells containing a transition metal, a method for manufacturing the same, and a fuel cell using the same. The catalyst for fuel cells includes hollow alloy particles formed by supporting platinum-transition metal alloy particles on a carbon support, thereby fueling the fuel cell. When operating a battery, the large adsorption energy of Pt in a commercially available Pt/C catalyst with oxygen, a reactant, prevents the reaction from being delayed until the final reaction, and the reaction rate can be increased by reducing the adsorption energy between Pt and oxygen.
Description
본 발명은 전이금속을 포함하는 연료전지용 촉매, 이의 제조방법 및 이를 포함하는 연료전지에 관한 것이다.The present invention relates to a catalyst for fuel cells containing a transition metal, a method for manufacturing the same, and a fuel cell containing the same.
기후 이상 문제가 대두됨에 따라 친환경 에너지에 대한 관심 및 수요가 증가하고 있다. 그 중에서도, 저온에서 구동이 가능하고, 출력밀도와 효율이 높은 고분자 전해질막 연료전지에 대한 연구가 활발히 진행되고 있다. 고분자 전해질막 연료전지를 구동하기 위해서는 촉매가 필요하고, 상기 촉매로는 탄소 지지체 위에 백금(Pt) 나노입자를 담지한 Pt/C 촉매가 많이 사용되고 있는데, 그 이유는 탄소 지지체의 높은 전도도 및 비표면적과 Pt 나노입자의 뛰어난 산소 환원 및 수소 산화 반응 활성 때문이다. 하지만, Pt/C 촉매의 Pt는 반응물질인 산소와의 흡착 에너지가 크기 때문에 최종 반응까지의 반응속도를 늦추는 문제점이 있다. 현재 전이금속을 Pt과 합금하여 Pt-산소 간 흡착 에너지를 줄이는 연구가 진행되고 있으나, 합금의 양이 많아지면 흡착 에너지가 크게 감소하여 역으로 산소를 흡착하지 못하는 문제가 있다. 따라서, 합금 양에 대한 최적화된 연구가 필요하다.As climate problems emerge, interest in and demand for eco-friendly energy is increasing. Among them, research is being actively conducted on polymer electrolyte membrane fuel cells that can be operated at low temperatures and have high power density and efficiency. A catalyst is required to drive a polymer electrolyte membrane fuel cell, and a Pt/C catalyst containing platinum (Pt) nanoparticles supported on a carbon support is widely used as the catalyst due to the high conductivity and specific surface area of the carbon support. This is due to the excellent oxygen reduction and hydrogen oxidation reaction activities of Pt nanoparticles. However, the Pt of the Pt/C catalyst has a problem of slowing down the reaction rate until the final reaction because the adsorption energy of the Pt with oxygen, a reactant, is high. Currently, research is being conducted to reduce the adsorption energy between Pt and oxygen by alloying a transition metal with Pt, but as the amount of alloy increases, the adsorption energy decreases significantly, which leads to the problem that oxygen cannot be adsorbed. Therefore, optimized research on alloy amount is needed.
본 발명은 상기와 같은 문제점을 해결하기 위하여, 탄소 지지체 위에 Pt-전이금속 합금 입자를 담지시킨 연료전지용 촉매를 제조할 수 있도록 하여, 연료전지 구동시 상용되는 Pt/C 촉매의 Pt이 반응물질인 산소와의 큰 흡착 에너지로 최종 반응까지의 반응이 늦춰지는 것을 방지하고, Pt-산소 간 흡착 에너지를 줄여 반응속도를 증가시킬 수 있는 고활성 합금 촉매의 제조방법을 제공하는 데 그 목적이 있다.In order to solve the above problems, the present invention makes it possible to manufacture a catalyst for fuel cells in which Pt-transition metal alloy particles are supported on a carbon support, and Pt of the Pt/C catalyst commonly used when driving a fuel cell is the reactant. The purpose is to provide a method for producing a highly active alloy catalyst that can prevent the reaction from being delayed until the final reaction due to the large adsorption energy with oxygen and increase the reaction rate by reducing the adsorption energy between Pt and oxygen.
상기와 같은 목적을 달성하기 위하여, 본 발명은 (1) 유기용매에 전이금속 전구체 및 탄소 지지체를 녹인 후, 균일하게 분산하여 분산액을 제조하는 단계; (2) 상기 분산액을 승온한 후, 환원제를 첨가하여 제1용액을 제조하는 단계; (3) 유기용매에 백금 전구체를 녹인 후, 염기를 첨가하여 pH를 조절한 제2용액을 상기 제1용액에 넣고, 열처리하는 단계; (4) 열처리한 용액을 상온으로 식힌 후, 세척하고 건조하여 분말상태의 시료를 수득하는 단계; 및 (5) 상기 시료를 산 처리하는 단계;를 포함하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법을 제공한다.In order to achieve the above object, the present invention includes the steps of (1) dissolving a transition metal precursor and a carbon support in an organic solvent and dispersing them uniformly to prepare a dispersion; (2) preparing a first solution by raising the temperature of the dispersion and adding a reducing agent; (3) dissolving the platinum precursor in an organic solvent, adding a second solution whose pH was adjusted by adding a base to the first solution, and heat treating it; (4) cooling the heat-treated solution to room temperature, washing and drying to obtain a powder sample; and (5) treating the sample with acid. A method for manufacturing a catalyst for a fuel cell including hollow alloy particles is provided.
또한, 본 발명은 상기 제조방법으로 제조된 중공형 합금입자를 포함하는 연료전지용 촉매를 제공한다.In addition, the present invention provides a catalyst for fuel cells containing hollow alloy particles manufactured by the above manufacturing method.
또한, 본 발명은 상기 연료전지용 촉매를 포함하는 연료전지를 제공한다.Additionally, the present invention provides a fuel cell including the fuel cell catalyst.
본 발명에 따른 연료전지용 촉매의 제조방법은 백금 전구체 용액의 pH를 조절하는 간단한 공정으로, 상용 Pt/C 촉매를 제조하는 폴리올 공정과 비교하여 반응 시간이 짧고, 반응 온도가 낮은 장점이 있다.The method for producing a catalyst for fuel cells according to the present invention is a simple process of adjusting the pH of a platinum precursor solution, and has the advantages of a short reaction time and low reaction temperature compared to the polyol process for producing a commercial Pt/C catalyst.
또한, 본 발명에 따른 연료전지용 촉매는 백금 나노입자와 산소 간의 흡착에너지를 간단한 pH 조절 공정을 통해 조절하였으며, 최적의 pH를 찾음으로써 상용 Pt/C 촉매보다 산소 환원 반응 활성이 크게 향상되어, 연료전지의 성능을 향상시킬 수 있다.In addition, the fuel cell catalyst according to the present invention adjusts the adsorption energy between platinum nanoparticles and oxygen through a simple pH adjustment process, and by finding the optimal pH, the oxygen reduction reaction activity is greatly improved compared to the commercial Pt/C catalyst, thereby improving the fuel cell catalyst. Battery performance can be improved.
도 1은 본 발명에 따른 연료전지용 촉매 및 비교예의 촉매를 대상으로 X선 회절 분석(X-ray Diffraction; XRD)을 진행한 결과이다.
도 2는 본 발명에 따른 연료전지용 촉매 및 비교예의 촉매를 대상으로 투과전자현미경 분석(Transmission electron microscopy; TEM), EDS mapping 및 line profile images를 진행한 결과이다.
도 3은 본 발명에 따른 연료전지용 촉매 및 비교예의 촉매를 대상으로 X선 광전자 분광법(X-ray Photoelectron spectroscopy; XPS) 분석을 진행한 결과이다.
도 4는 본 발명에 따른 연료전지용 촉매 및 비교예의 촉매를 대상으로 전기화학특성을 분석한 활성을 나타낸 결과로, 도 4(a)는 순환전압전류법(Cyclic voltammetry; CV), 도 4(b)는 산소 환원 반응(Oxygen reduction reaction; ORR) 활성 비교, 도 4(c)는 촉매 활성(Mass activity; MA), 도 4(d)는 전기화학 임피던스 분광법(Electrochemical impedance spectroscopy; EIS) 결과를 각각 나타낸 것이다.Figure 1 shows the results of X-ray diffraction (XRD) analysis on the fuel cell catalyst according to the present invention and the catalyst of the comparative example.
Figure 2 shows the results of transmission electron microscopy (TEM), EDS mapping, and line profile images for the fuel cell catalyst according to the present invention and the catalyst of the comparative example.
Figure 3 shows the results of X-ray photoelectron spectroscopy (XPS) analysis of the fuel cell catalyst according to the present invention and the catalyst of the comparative example.
Figure 4 shows the results of analyzing the electrochemical characteristics of the catalyst for fuel cells according to the present invention and the catalyst of the comparative example, Figure 4(a) is cyclic voltammetry (CV), Figure 4(b) ) is a comparison of oxygen reduction reaction (ORR) activity, Figure 4(c) is a comparison of catalytic activity (Mass activity (MA)), and Figure 4(d) is a comparison of electrochemical impedance spectroscopy (EIS) results, respectively. It is shown.
이하, 본 발명을 보다 구체적으로 설명하기 위하여 본 발명에 따른 바람직한 실시예를 첨부된 도면을 참조하여 보다 상세하게 설명한다. 그러나, 본 발명은 여기서 설명되어지는 실시예에 한정되지 않고 다른 형태로 구체화될 수도 있다.Hereinafter, in order to explain the present invention in more detail, preferred embodiments according to the present invention will be described in more detail with reference to the attached drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms.
본 발명은 (1) 유기용매에 전이금속 전구체 및 탄소 지지체를 녹인 후, 균일하게 분산하여 분산액을 제조하는 단계; (2) 상기 분산액을 승온한 후, 환원제를 첨가하여 제1용액을 제조하는 단계; (3) 유기용매에 백금 전구체를 녹인 후, 염기를 첨가하여 pH를 조절한 제2용액을 상기 제1용액에 넣고, 열처리하는 단계; (4) 열처리한 용액을 상온으로 식힌 후, 세척하고 건조하여 분말상태의 시료를 수득하는 단계; 및 (5) 상기 시료를 산 처리하는 단계;를 포함하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법을 제공한다. The present invention includes the steps of (1) dissolving a transition metal precursor and a carbon support in an organic solvent and dispersing them uniformly to prepare a dispersion; (2) preparing a first solution by raising the temperature of the dispersion and adding a reducing agent; (3) dissolving the platinum precursor in an organic solvent, adding a second solution whose pH was adjusted by adding a base to the first solution, and heat treating it; (4) cooling the heat-treated solution to room temperature, washing and drying to obtain a powder sample; and (5) treating the sample with acid. A method for manufacturing a catalyst for a fuel cell including hollow alloy particles is provided.
상기 (1) 단계 및 (3)단계에서, 상기 유기용매는 에틸렌 글리콜(ethylene glycol), 에탄올, 메탄올, 아이소프로필 알코올(isopropyl alcohol), 아세트산에틸(ethyl acetate), 디메틸포름아미드(Dimethylformamide) 및 NMP(N-methylpyrrolidone) 중 적어도 어느 하나 이상을 포함할 수 있다.In steps (1) and (3), the organic solvent is ethylene glycol, ethanol, methanol, isopropyl alcohol, ethyl acetate, dimethylformamide, and NMP. It may contain at least one or more of (N-methylpyrrolidone).
상기 (1) 단계에서, 상기 전이금속 전구체는 Ni, Co, Fe, Cr, Cu, Ru, Pd, Sn, V, Mo, W 및 Ir 중 적어도 하나 이상을 포함할 수 있다.In step (1), the transition metal precursor may include at least one of Ni, Co, Fe, Cr, Cu, Ru, Pd, Sn, V, Mo, W, and Ir.
구체적으로, 상기 전이금속 전구체는 NiCl2ㆍ6H2O, CoCl2ㆍ6H2O, NiBr2, NiCl2, RuCl3, CoCl2, FeCl2, FeCl3, FeCl2ㆍ4H2O,FeCl3ㆍ6H2O, CrCl3, CrCl2, CrCl3ㆍ6H2O, CuBr2, CuCl2, CuCl2ㆍ2H2O, PdCl2, PdCl3, SnCl2, SnBr2, SnCl4, SnCl2ㆍ2H2O, MoCl2, MoCl3, WCl4, WCl6 및 IrCl3 중 적어도 어느 하나 이상을 포함할 수 있다.Specifically, the transition metal precursor is NiCl 2 ㆍ6H 2 O, CoCl 2 ㆍ6H 2 O, NiBr 2 , NiCl 2, RuCl 3 , CoCl 2 , FeCl 2 , FeCl 3 , FeCl 2 ㆍ4H 2 O, FeCl 3 ㆍ 6H 2 O, CrCl 3 , CrCl 2 , CrCl 3 ㆍ6H 2 O, CuBr 2 , CuCl 2 , CuCl 2 ㆍ2H 2 O, PdCl 2 , PdCl 3 , SnCl 2 , SnBr 2 , SnCl 4 , SnCl 2 ㆍ2H 2 It may include at least one of O, MoCl 2 , MoCl 3 , WCl 4 , WCl 6 , and IrCl 3 .
상기 (1) 단계에서, 상기 탄소 지지체는 카본블랙, 탄소분말, 아세틸렌블랙, 케첸블랙, 활성탄소, 카본나노튜브, 카본나노파이버, 카본나노와이어, 카본나노혼, 카본에어로겔, 카본크레로겔 및 카본나노링 중 적어도 하나 이상을 포함할 수 있다. 구체적으로, 상기 탄소 지지체는 카본블랙, 케첸블랙 또는 카본나노튜브일 수 있다.In step (1), the carbon support includes carbon black, carbon powder, acetylene black, Ketjen black, activated carbon, carbon nanotubes, carbon nanofibers, carbon nanowires, carbon nanohorns, carbon airgel, carbon cerogel, and It may include at least one of carbon nanorings. Specifically, the carbon support may be carbon black, Ketjen black, or carbon nanotubes.
상기 (2) 단계에서, 상기 환원제는 히드라진 수화물(N2H4·H2O), 수소화붕소나트륨, 에틸렌글리콜, 디에틸렌글리콜, 트리에틸렌글리콜, 테트라에틸렌글리콜, 디프로필렌글리콜, 프로판디올, 부탄디올 및 포름알데하이드 중 적어도 하나 이상을 포함할 수 있다. 구체적으로, 상기 환원제는 히드라진 수화물(N2H4·H2O) 또는 수소화붕소나트륨일 수 있다.In step (2), the reducing agent is hydrazine hydrate (N 2 H 4 ·H 2 O), sodium borohydride, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, propanediol, butanediol. and formaldehyde. Specifically, the reducing agent may be hydrazine hydrate (N 2 H 4 ·H 2 O) or sodium borohydride.
또한, 상기 (2) 단계에서는 상기 분산액의 승온시, 온도는 60℃~80℃일 수 있고, 상기 분산액을 승온한 후 환원제를 첨가하여, 탄소 지지체 상에 담지된 전이금속을 포함하는 제1용액을 제조할 수 있다.In addition, in step (2), when the temperature of the dispersion is raised, the temperature may be 60°C to 80°C, and a reducing agent is added after raising the temperature of the dispersion to form a first solution containing a transition metal supported on a carbon support. can be manufactured.
상기 (3) 단계에서, 상기 백금 전구체는 염화백금(PtCl4), 소듐 테트라클로로 플레티네이트(Na2PtCl4), 포타슘 테트라클로로 플레티네이트(K2PtCl4), 백금 클로라이드(PtCl2), 염화백금산(H2PtCl6) 사염화백금산(H2PtCl4) 및 사아민클로로백금(Pt(NH3)4Cl2) 중 적어도 하나 이상을 포함할 수 있으며, 상기 열처리하는 단계는 60∼80 ℃에서 1∼2시간 동안 수행되는 것일 수 있다.In step (3), the platinum precursor is platinum chloride (PtCl 4 ), sodium tetrachloro platinate (Na 2 PtCl 4 ), potassium tetrachloro platinate (K 2 PtCl 4 ), and platinum chloride (PtCl 2 ). , chloroplatinic acid (H 2 PtCl 6 ), tetrachloroplatinic acid (H 2 PtCl 4 ), and tetraaminechloroplatinum (Pt(NH 3 ) 4 Cl 2 ), and the heat treatment step may be performed at 60 to 80 °C. It may be performed at ℃ for 1 to 2 hours.
또한, 상기 (3) 단계에서, 상기 제2용액은 염기를 첨가하여 pH를 9∼12로 조절하는 것일 수 있다. 이 때, 상기 염기는 수산화나트륨(NaOH) 또는 수산화칼륨(KOH)일 수 있다.Additionally, in step (3), the pH of the second solution may be adjusted to 9 to 12 by adding a base. At this time, the base may be sodium hydroxide (NaOH) or potassium hydroxide (KOH).
본 발명의 일 실시예에 따르면, 상기 중공형 합금입자는 상기 제2용액의 pH가 증가할수록 원자 반지름이 상대적으로 작은 Ni이 Pt 자리를 치환하면서 Pt과 Ni이 더 많이 반응하여 합금정도가 증가하는 것일 수 있다.According to one embodiment of the present invention, as the pH of the second solution increases, Ni, which has a relatively small atomic radius, replaces the Pt site and Pt and Ni react more, increasing the alloying degree. It could be.
상기 (4) 단계에서, 상기 건조는 40∼60 ℃에서 3∼5시간 수행되는 것일 수 있다.In step (4), the drying may be performed at 40 to 60 ° C. for 3 to 5 hours.
상기 (5) 단계에서, 상기 산은 염산, 황산, 질산, 불산, 옥살산, 아세트산 및 글리콜산 중 적어도 하나 이상을 포함할 수 있다. 구체적으로, 상기 (5) 단계에서, 상기 건조한 시료에 5∼20분 동안 산 처리하여 중공형 합금입자를 포함하는 촉매를 합성하는 것일 수 있다.In step (5), the acid may include at least one of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, oxalic acid, acetic acid, and glycolic acid. Specifically, in step (5), a catalyst containing hollow alloy particles may be synthesized by treating the dried sample with acid for 5 to 20 minutes.
또한, 본 발명은 상기 제조방법에 따라 제조된 중공형 합금입자를 포함하는 연료전지용 촉매를 제공한다.Additionally, the present invention provides a catalyst for fuel cells containing hollow alloy particles manufactured according to the above manufacturing method.
상기 촉매는 복수 개의 중공형 합금입자로 이루어져 있고, 상기 합금입자는 Pt 및 1종 이상의 전이금속과의 합금인 것일 수 있다.The catalyst consists of a plurality of hollow alloy particles, and the alloy particles may be an alloy of Pt and one or more transition metals.
상기 전이금속은 Ni, Co, Fe, Cr, Cu, Ru, Pd, Sn, V, Mo, W 및 Ir 중 적어도 하나 이상을 포함할 수 있다. 구체적으로, 상기 전이금속은 Ni, Co 또는 Fe일 수 있다.The transition metal may include at least one of Ni, Co, Fe, Cr, Cu, Ru, Pd, Sn, V, Mo, W, and Ir. Specifically, the transition metal may be Ni, Co, or Fe.
상기 중공형 합금입자의 입자간 평균 거리는 0.2 내지 0.25 nm일 수 있다.The average distance between particles of the hollow alloy particles may be 0.2 to 0.25 nm.
상기 촉매의 평균 입경은 9 내지 15 nm일 수 있다. 구체적으로, 상기 촉매의 평균 입경은 10 내지 12 nm일 수 있다.The average particle diameter of the catalyst may be 9 to 15 nm. Specifically, the average particle diameter of the catalyst may be 10 to 12 nm.
상기 중공형 합금입자를 포함하는 연료전지용 촉매는 종래의 Pt/C 촉매의 Pt이 반응물질인 산소와의 큰 흡착 에너지로 최종 반응까지의 반응이 늦춰지는 것을 방지하고, Pt-산소 간 흡착 에너지를 줄여 반응속도를 증가시킬 수 있는 고활성 합금 촉매로서 활용될 수 있다. 또한, 중공형 합금입자의 중공은 물의 저장 공간으로 활용될 수 있으며, 중공형 합금입자 입자 사이에 형성된 큰 기공은 효율적인 수분 배출 및 촉매 층에서의 용이한 산소 전달 효과를 제공할 수 있다.The fuel cell catalyst containing the hollow alloy particles prevents the reaction from being delayed until the final reaction due to the large adsorption energy of Pt with oxygen, a reactant, in the conventional Pt/C catalyst, and increases the adsorption energy between Pt and oxygen. It can be used as a highly active alloy catalyst that can increase the reaction rate by reducing the reaction rate. In addition, the cavities of the hollow alloy particles can be used as water storage spaces, and the large pores formed between the hollow alloy particles can provide efficient moisture discharge and easy oxygen transfer in the catalyst layer.
또한, 본 발명은 상기 연료전지용 촉매를 포함하는 연료전지를 제공한다.Additionally, the present invention provides a fuel cell including the fuel cell catalyst.
이하, 본 발명의 이해를 돕기 위하여 실시예를 들어 상세하게 설명하기로 한다. 다만 하기의 실시예는 본 발명의 내용을 예시하는 것일 뿐 본 발명의 범위가 하기 실시예에 한정되는 것은 아니다. 본 발명의 실시예는 당업계에서 평균적인 지식을 가진 자에게 본 발명을 보다 완전하게 설명하기 위해 제공되는 것이다.Hereinafter, the present invention will be described in detail through examples to aid understanding. However, the following examples only illustrate the content of the present invention and the scope of the present invention is not limited to the following examples. Examples of the present invention are provided to more completely explain the present invention to those skilled in the art.
<실시예 1> 중공형 Pt/Ni 합금입자(h-PtNi/C)를 포함하는 촉매의 제조<Example 1> Preparation of catalyst containing hollow Pt/Ni alloy particles (h-PtNi/C)
중공형 Pt/Ni 합금입자(h-PtNi/C)를 포함하는 촉매는 낮은 반응 온도, 짧은 반응 시간으로 간단한 one-pot 공정으로 합성하였다. 먼저, 탄소 위에 Ni을 담지한 후 금속 Ni을 Pt 용액과 반응시켜주었다. 용매인 에틸렌글리콜(Ethylene glycol) 60 mL에 NiCl2·6H2O, Vulcan carbon XC-72R을 녹인 후, 초음파 분쇄기로 균일하게 분산시켜주었다. 분산한 용액을 80 ℃로 올려준 후, 환원제인 N2H4·H2O, 0.5 M NaOH를 넣어주어 Ni을 탄소 위에 담지하였다. 연속으로 에틸렌글리콜에 PtCl4를 녹인 용액 pH를 0.5 M NaOH로 맞춘 후 Ni이 담지된 용액에 1 mL/min 속도로 넣어주었고, 80 ℃에서 1시간동안 열처리를 진행하였다. 반응 완료된 용액을 상온으로 식힌 후 1 L EtOH로 세척하였고, 50 ℃ 진공오븐에서 건조하였다. 건조한 시료를 2 M HCl에서 10분 동안 산 처리하여 최종적으로 h-PtNi/C 촉매를 합성하였다.A catalyst containing hollow Pt/Ni alloy particles (h-PtNi/C) was synthesized through a simple one-pot process with low reaction temperature and short reaction time. First, Ni was supported on carbon and then metallic Ni was reacted with the Pt solution. NiCl 2 ·6H 2 O and Vulcan carbon After raising the dispersed solution to 80°C, reducing agents N 2 H 4 ·H 2 O and 0.5 M NaOH were added to support Ni on carbon. The pH of the solution in which PtCl 4 was continuously dissolved in ethylene glycol was adjusted to 0.5 M NaOH, then added to the Ni-supported solution at a rate of 1 mL/min, and heat treatment was performed at 80°C for 1 hour. The reaction solution was cooled to room temperature, washed with 1 L EtOH, and dried in a vacuum oven at 50°C. The dried sample was treated with acid in 2 M HCl for 10 minutes to finally synthesize h-PtNi/C catalyst.
이 때, 상기 Pt 전구체 용액의 pH에 따른 합금 정도와 전기화학적 활성을 비교하기 위해 Pt 전구체 용액의 pH를 다양하게 조절하였다. pH를 11로 조절하여 촉매를 합성하였고, h-PtNi/C(11)로 명명하였다. At this time, the pH of the Pt precursor solution was adjusted variously to compare the degree of alloying and electrochemical activity according to the pH of the Pt precursor solution. The catalyst was synthesized by adjusting the pH to 11, and was named h-PtNi/C(11).
<실시예 2> h-PtNi/C(9) 촉매의 제조<Example 2> Preparation of h-PtNi/C(9) catalyst
Pt 전구체 용액의 pH를 9로 조절한 것을 제외하고는 실시예 1과 동일한 방법으로 연료전지용 촉매를 제조하였다.A fuel cell catalyst was prepared in the same manner as Example 1, except that the pH of the Pt precursor solution was adjusted to 9.
<실시예 3> h-PtNi/C(10) 촉매의 제조<Example 3> Preparation of h-PtNi/C(10) catalyst
Pt 전구체 용액의 pH를 10으로 조절한 것을 제외하고는 실시예 1과 동일한 방법으로 연료전지용 촉매를 제조하였다.A catalyst for fuel cells was prepared in the same manner as Example 1, except that the pH of the Pt precursor solution was adjusted to 10.
<실시예 4> h-PtNi/C(12) 촉매의 제조<Example 4> Preparation of h-PtNi/C(12) catalyst
Pt 전구체 용액의 pH를 12으로 조절한 것을 제외하고는 실시예 1과 동일한 방법으로 연료전지용 촉매를 제조하였다.A fuel cell catalyst was prepared in the same manner as Example 1, except that the pH of the Pt precursor solution was adjusted to 12.
<실시예 5> h-PtNi/C(0.5) 촉매의 제조<Example 5> Preparation of h-PtNi/C(0.5) catalyst
Pt 전구체 용액의 pH를 0.5로 조절한 것을 제외하고는 실시예 1과 동일한 방법으로 연료전지용 촉매를 제조하였다.A catalyst for a fuel cell was prepared in the same manner as Example 1, except that the pH of the Pt precursor solution was adjusted to 0.5.
<비교예> 백금/C 촉매 제조<Comparative example> Preparation of platinum/C catalyst
Pt/C(20 wt%)의 백금 촉매를 상업적으로 구입하였다.A platinum catalyst of Pt/C (20 wt%) was purchased commercially.
<실험예 1> 구조 분석<Experimental Example 1> Structural analysis
실험예 1-1. XRD(X-ray Diffraction)Experimental Example 1-1. XRD(X-ray Diffraction)
본 발명에 따른 연료전지용 촉매의 구조를 확인하기 위해, 본 발명에 따른 실시예의 촉매 및 비교예의 촉매를 대상으로 X선 회절 분석(X-ray diffraction, XRD)을 수행하였으며, 그 결과는 도 1에 나타내었다.In order to confirm the structure of the catalyst for fuel cells according to the present invention, X-ray diffraction (XRD) analysis was performed on the catalyst of the example and the comparative example according to the present invention, and the results are shown in indicated.
도 1은 pH를 달리하여 실시예에서 제조한 h-PtNi/C의 결정구조를 XRD 기술을 통해 분석한 데이터이다. 도 1(a)는 10∼80°로 측정한 결과이고, 도 1(b)는 Pt(111)면을 확대한 결과이다. 도 1(a)를 살펴보면, 시료 모두 20∼30°부근에서 graphite carbon peak를 확인할 수 있다. 또한, 도 1(b)에서 Pt(111)면을 확대한 결과를 살펴보면, Pt 전구체 용액의 pH가 증가할수록 peak가 오른쪽으로 이동하는 것을 관찰하였다. 이는 원자 반지름이 상대적으로 작은 Ni이 Pt자리를 치환하면서 나타난 결과로 pH가 증가할수록 Pt과 Ni이 더 많이 반응하여 합금정도가 증가하는 것을 확인할 수 있다.Figure 1 shows data analyzing the crystal structure of h-PtNi/C prepared in Examples at different pHs using XRD technology. Figure 1(a) is the result of measurement from 10 to 80°, and Figure 1(b) is the result of enlarging the Pt (111) surface. Looking at Figure 1(a), graphite carbon peaks can be seen around 20-30° in all samples. Additionally, looking at the enlarged results of the Pt (111) surface in Figure 1(b), it was observed that the peak shifted to the right as the pH of the Pt precursor solution increased. This is a result of Ni, which has a relatively small atomic radius, replacing the Pt site. It can be seen that as pH increases, Pt and Ni react more and the degree of alloying increases.
실험예 1-2. TEM(Transmission electron microscopy)Experimental Example 1-2. Transmission electron microscopy (TEM)
도 2는 본 발명에 따른 실시예의 촉매 및 비교예의 촉매인 h-PtNi/C의 표면 형상 및 입자 크기를 투과전자현미경(Transmission electron microscope, TEM)을 통해 분석한 데이터, EDS mapping 및 line profile image이다. 도 2의 TEM 이미지를 통해 hollow 구조를 갖는 PtNi 촉매 입자들이 탄소 위에 고르게 분산 및 담지되어 있는 것을 관찰하였다. pH가 증가할수록 촉매 격자 간격이 감소하는 것을 통해 Pt과 Ni이 더 많이 반응한 것을 다시 확인하였다. 또한, 도 2의 EDS mapping 및 line profile image를 통해 pH와 상관없이 모든 촉매 입자들이 hollow 구조를 갖는 것을 확인하였다. 촉매 입자들의 size distribution을 한 결과, pH가 증가할수록 입자 크기가 감소하는 경향을 나타내었다.Figure 2 shows data, EDS mapping, and line profile images analyzed through a transmission electron microscope (TEM) on the surface shape and particle size of h-PtNi/C, which is a catalyst of Examples and Comparative Examples according to the present invention. . Through the TEM image in Figure 2, it was observed that PtNi catalyst particles with a hollow structure were evenly dispersed and supported on carbon. It was confirmed again that as pH increased, the catalyst lattice spacing decreased, showing that Pt and Ni reacted more. In addition, through EDS mapping and line profile image in Figure 2, it was confirmed that all catalyst particles had a hollow structure regardless of pH. As a result of the size distribution of catalyst particles, the particle size tended to decrease as pH increased.
실험예 1-3. XPS(X-ray Photoelectron spectroscopy)Experimental Example 1-3. X-ray photoelectron spectroscopy (XPS)
도 3은 pH가 다른 h-PtNi/C 촉매와 상용 Pt/C 촉매의 Pt4f XPS spectrum이다. 도 3을 살펴보면, Pt4f7/2에 해당하는 피크의 결합 에너지(binding energy)는 상용 Pt/C (71.89 eV), pH x (71.89 eV), pH 9(71.91 eV), pH 10(71.95 eV), pH 11(72 eV), pH 12(71.93 eV)이다. 합성한 h-PtNi/C 촉매 모두 상용 Pt/C 촉매보다 결합 에너지가 큰 것을 알 수 있으며, pH가 증가할수록 결합 에너지가 증가하다가 pH 11을 기점으로 감소하는 것을 확인하였다. 상용 Pt/C보다 결합 에너지가 큰 것은 Pt과 반응물질인 산소 간 흡착에너지가 감소한 것을 의미한다. 따라서, pH가 증가할수록 Pt-산소 흡착 에너지가 감소하였고, pH 11을 기점으로 흡착 에너지가 다시 증가하는 것을 알 수 있다. 이를 통해, pH 11에서 최적의 Pt, Ni 합금이 이루어졌고, 전기화학적 활성 또한 pH 11에서 최대 활성을 보이는 것을 확인할 수 있다.Figure 3 shows the Pt4f XPS spectrum of h-PtNi/C catalyst and commercial Pt/C catalyst with different pH. Looking at Figure 3, the binding energy of the peak corresponding to Pt4f 7/2 is commercial Pt/C (71.89 eV), pH x (71.89 eV), pH 9 (71.91 eV), and pH 10 (71.95 eV). , pH 11 (72 eV), pH 12 (71.93 eV). It can be seen that all of the synthesized h-PtNi/C catalysts have larger binding energies than commercial Pt/C catalysts, and it was confirmed that the binding energy increased as pH increased and then decreased starting at pH 11. The fact that the binding energy is greater than that of commercial Pt/C means that the adsorption energy between Pt and oxygen, a reactant, is reduced. Therefore, it can be seen that as the pH increases, the Pt-oxygen adsorption energy decreases, and starting from pH 11, the adsorption energy increases again. Through this, it can be seen that the optimal Pt and Ni alloy was achieved at pH 11, and the electrochemical activity also showed maximum activity at pH 11.
<실험예 2> 전기화학분석<Experimental Example 2> Electrochemical analysis
본 발명에 따른 연료전지용 촉매의 전기화학 특성을 확인하기 위해, 본 발명에 따른 실시예의 촉매 및 비교예의 촉매를 대상으로 연료전지용 환원극 촉매로써 산소환원 반응활성이 측정하는 전기화학분석을 하기와 같이 수행하였으며, 그 결과는 도 4에 나타내었다.In order to confirm the electrochemical properties of the catalyst for fuel cells according to the present invention, electrochemical analysis was performed to measure the oxygen reduction reaction activity of the catalysts of the Examples and Comparative Examples according to the present invention as a cathode catalyst for fuel cells as follows. This was performed, and the results are shown in Figure 4.
도 4는 상용 Pt/C 촉매와 합성한 h-PtNi/C 촉매의 전기화학 분석 결과 데이터이다. 촉매의 전기화학적 활성 면적을 비교하기 위하여 Ar 기체로 포화된 0.1M HClO4용액으로 이루어진 Cell에서 0.05 ~ 1.2 V vs. RHE 의 전압 범위를 50 mV/s로 주사하여 순환 전압전류법(Cyclic Voltammetry)을 진행한 결과, 도 4(a)와 같은 데이터를 얻을 수 있었다. 도 4(a)를 살펴보면, 수소 탈착 범위인 0.05 ∼0.35 V vs. RHE에서 나타난 산화 피크 면적을 백금 양으로 나누어 전기화학적 활성 면적을 계산한 결과 55.6(pH 11), 50.3(pH 10), 43.2(pH 9), 33.9(pH x), 20.0(pH 12)m2/gPt로 pH가 증가할수록 활성 면적이 증가하다가 pH 11을 기점으로 감소하는 것을 확인할 수 있다.Figure 4 shows electrochemical analysis results of a commercial Pt/C catalyst and a synthesized h-PtNi/C catalyst. To compare the electrochemically active area of the catalyst , 0.05 ~ 1.2 V vs. As a result of performing cyclic voltammetry by scanning the RHE voltage range at 50 mV/s, data as shown in Figure 4(a) was obtained. Looking at Figure 4(a), the hydrogen desorption range of 0.05 ~ 0.35 V vs. The electrochemically active area was calculated by dividing the oxidation peak area shown in RHE by the amount of platinum, and the results were 55.6 (pH 11), 50.3 (pH 10), 43.2 (pH 9), 33.9 (pH x), 20.0 (pH 12) m 2 It can be seen that as the pH increases with /gPt, the active area increases and then decreases starting from pH 11.
촉매의 산소 환원 반응 활성을 비교하기 위하여 O2 기체가 포화된 0.1 M HClO4 용액에서 0.05 ∼1.2 V vs RHE 전압 범위를 5 mV/s 주사했고, 이를 도 4(b)에 나타내었다. 도 4(b)를 참고하면, 산소 환원 반응 활성을 평가하는 대표적인 지표인 반파장전위(E 1/2)를 비교한 결과, 853 mV(pH 11), 844 mV(pH 10), 837 mV(pH 9), 825 mV(pH x), 806 mV(pH 12), 820 mV(상용 Pt/C)로 나타났다. pH가 증가할수록 Pt-산소 간 결합에너지가 감소하면서 상용 Pt/C 촉매보다 활성이 증가하는 것을 관찰하였고, pH 11에서 결합에너지가 최적화되어 최고의 성능을 보이는 것을 확인할 수 있다.To compare the oxygen reduction reaction activity of the catalyst, a voltage range of 0.05 to 1.2 V vs RHE was scanned at 5 mV/s in a 0.1 M HClO 4 solution saturated with O 2 gas, and this is shown in Figure 4(b). Referring to Figure 4(b), as a result of comparing the half-wave potential (E 1/2), which is a representative indicator for evaluating oxygen reduction reaction activity, 853 mV (pH 11), 844 mV (pH 10), 837 mV ( pH 9), 825 mV (pH x), 806 mV (pH 12), 820 mV (commercial Pt/C). It was observed that as pH increases, the binding energy between Pt and oxygen decreases and the activity increases compared to commercial Pt/C catalysts. It can be seen that the binding energy is optimized at pH 11, showing the best performance.
도 4(c)는 실제 사용한 백금 양 대비 활성을 나타내는 촉매 활성(MA)(@0.85 V vs RHE)로 합금 촉매의 활성을 평가하는 대표적인 지표이다. 합성한 촉매 모두 MA가 상용 Pt/C 촉매보다 9.3배(pH 11), 7.6배(pH 10), 6.2배(pH 9), 4.3배(pH x), 3.3배(pH 12) 높은 것을 확인할 수 있다.Figure 4(c) is a representative indicator for evaluating the activity of an alloy catalyst by catalytic activity (MA) (@0.85 V vs RHE), which represents the activity compared to the amount of platinum actually used. It can be seen that the MA of all synthesized catalysts is 9.3 times (pH 11), 7.6 times (pH 10), 6.2 times (pH 9), 4.3 times (pH x), and 3.3 times (pH 12) higher than that of commercial Pt/C catalysts. there is.
도 4(d)는 전기화학 임피던스 분광법(EIS) 측정 결과이다. 각 촉매의 Rct값은 47.0 Ω(pH 11), 50.4 Ω(pH 10), 55.4 Ω(pH 9), 65.7(pH x), 79.0 Ω(pH 12), 67.9 Ω(상용 Pt/C)으로, pH가 증가할수록 Rct 값이 감소하였고, 상용 Pt/C 촉매보다 작은 Rct 값을 가지는 것을 확인할 수 있다. 한편, pH 12의 경우 Pt-Ni간 흡착 에너지가 너무 작아 Rct 값이 증가하는 것을 알 수 있다.Figure 4(d) is the electrochemical impedance spectroscopy (EIS) measurement result. The R ct values of each catalyst were 47.0 Ω (pH 11), 50.4 Ω (pH 10), 55.4 Ω (pH 9), 65.7 (pH x), 79.0 Ω (pH 12), 67.9 Ω (commercial Pt/C). , the R ct value decreased as the pH increased, and it could be confirmed that the R ct value was smaller than that of the commercial Pt/C catalyst. Meanwhile, in the case of pH 12, the adsorption energy between Pt-Ni is too small, so it can be seen that the R ct value increases.
이상으로 본 발명 내용의 특정한 부분을 상세히 기술하였는 바, 당업계의 통상의 지식을 가진 자에게 있어서, 이러한 구체적 기술은 단지 바람직한 실시양태일 뿐이며, 이에 의해 본 발명의 범위가 제한되는 것이 아닌 점은 명백하다. 즉, 본 발명의 실질적인 범위는 첨부된 청구항들과 그것들의 등가물에 의하여 정의된다.As the specific parts of the present invention have been described in detail above, it is clear to those skilled in the art that these specific techniques are merely preferred embodiments and do not limit the scope of the present invention. do. That is, the practical scope of the present invention is defined by the appended claims and their equivalents.
Claims (17)
(2) 상기 분산액을 승온한 후, 환원제를 첨가하여 제1용액을 제조하는 단계;
(3) 유기용매에 백금 전구체를 녹인 후, 염기를 첨가하여 pH를 조절한 제2용액을 상기 제1용액에 넣고, 열처리하는 단계;
(4) 열처리한 용액을 상온으로 식힌 후, 세척하고 건조하여 분말상태의 시료를 수득하는 단계; 및
(5) 상기 시료를 산 처리하는 단계;를 포함하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.(1) dissolving the transition metal precursor and carbon support in an organic solvent and dispersing them uniformly to prepare a dispersion;
(2) preparing a first solution by raising the temperature of the dispersion and adding a reducing agent;
(3) dissolving the platinum precursor in an organic solvent, adding a second solution whose pH was adjusted by adding a base to the first solution, and heat treating it;
(4) cooling the heat-treated solution to room temperature, washing and drying to obtain a powder sample; and
(5) A method for producing a catalyst for a fuel cell containing hollow alloy particles, including the step of treating the sample with acid.
상기 (1) 단계에서는,
상기 전이금속 전구체는 Ni, Co, Fe, Cr, Cu, Ru, Pd, Sn, V, Mo, W, 및 Ir 중 하나의 금속을 포함하는 화합물로 이루어진 군에서 선택된 1종 이상인 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 1,
In step (1) above,
The transition metal precursor is a hollow material, characterized in that at least one selected from the group consisting of compounds containing one metal from Ni, Co, Fe, Cr, Cu, Ru, Pd, Sn, V, Mo, W, and Ir. Method for manufacturing a catalyst for fuel cells containing type alloy particles.
상기 전이금속 전구체는 NiCl2ㆍ6H2O, CoCl2ㆍ6H2O, NiBr2, NiCl2, RuCl3, CoCl2, FeCl2, FeCl3, FeCl2ㆍ4H2O, FeCl3ㆍ6H2O, CrCl3, CrCl2, CrCl3ㆍ6H2O, CuBr2, CuCl2, CuCl2ㆍ2H2O, PdCl2, PdCl3, SnCl2, SnBr2, SnCl4, SnCl2ㆍ2H2O, MoCl2, MoCl3, WCl4, WCl6, 및 IrCl3로 이루어진 군에서 선택된 1종 이상인 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 2,
The transition metal precursor is NiCl 2 ㆍ6H 2 O, CoCl 2 ㆍ6H 2 O, NiBr 2 , NiCl 2 , RuCl 3 , CoCl 2 , FeCl 2 , FeCl 3 , FeCl 2 ㆍ4H 2 O, FeCl 3 ㆍ6H 2 O , CrCl 3 , CrCl 2 , CrCl 3 ㆍ6H 2 O, CuBr 2 , CuCl 2 , CuCl 2 ㆍ2H 2 O, PdCl 2 , PdCl 3 , SnCl 2 , SnBr 2 , SnCl 4 , SnCl 2 ㆍ2H 2 O, MoCl 2 , MoCl 3 , WCl 4 , WCl 6 , and IrCl 3. A method for producing a catalyst for fuel cells containing hollow alloy particles, characterized in that at least one selected from the group consisting of.
상기 (1) 단계에서는,
상기 탄소 지지체는 카본블랙, 탄소분말, 아세틸렌블랙, 케첸블랙, 활성탄소, 카본나노튜브, 카본나노파이버, 카본나노와이어, 카본나노혼, 카본에어로겔, 카본크레로겔 및 카본나노링으로 이루어진 군에서 선택된 1종 이상인 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 1,
In step (1) above,
The carbon support is selected from the group consisting of carbon black, carbon powder, acetylene black, Ketjen black, activated carbon, carbon nanotubes, carbon nanofibers, carbon nanowires, carbon nanohorns, carbon airgel, carbon cerogel, and carbon nanorings. A method of manufacturing a catalyst for a fuel cell containing hollow alloy particles, characterized in that one or more selected types.
상기 (2) 단계에서는,
상기 환원제는 히드라진 수화물, 수소화붕소나트륨, 에틸렌글리콜, 디에틸렌글리콜, 트리에틸렌글리콜, 테트라에틸렌클리콜, 디프로필렌글리콜, 프로판디올, 부탄디올 및 포름알데하이드로 이루어진 군에서 선택된 1종 이상인 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 1,
In step (2) above,
The reducing agent is hollow, characterized in that at least one selected from the group consisting of hydrazine hydrate, sodium borohydride, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, propanediol, butanediol, and formaldehyde. Method for manufacturing a catalyst for fuel cells containing type alloy particles.
상기 (2) 단계에서는,
상기 분산액의 승온시, 온도는 60∼80 ℃인 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 1,
In step (2) above,
A method for producing a catalyst for fuel cells containing hollow alloy particles, characterized in that when the temperature of the dispersion is raised, the temperature is 60 to 80 ° C.
상기 (3) 단계에서는,
상기 백금 전구체는 염화백금(PtCl4), 소듐 테트라클로로 플레티네이트(Na2PtCl4), 포타슘 테트라클로로 플레티네이트(K2PtCl4), 백금 클로라이드(PtCl2), 염화백금산(H2PtCl6) 사염화백금산(H2PtCl4) 및 사아민클로로백금(Pt(NH3)4Cl2)으로 이루어진 군에서 선택된 1종 이상인 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 1,
In step (3) above,
The platinum precursor is platinum chloride (PtCl 4 ), sodium tetrachloro platinate (Na 2 PtCl 4 ), potassium tetrachloro platinate (K 2 PtCl 4 ), platinum chloride (PtCl 2 ), chloroplatinic acid (H 2 PtCl 6 ) Method for producing a catalyst for fuel cells containing hollow alloy particles, characterized in that at least one selected from the group consisting of tetrachloroplatinic acid (H 2 PtCl 4 ) and tetraaminechloroplatinum (Pt(NH 3 ) 4 Cl 2 ) .
상기 (3) 단계에서는,
상기 열처리하는 단계는 60∼80℃에서 1∼2시간 동안 수행되는 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 1,
In step (3) above,
A method for producing a catalyst for fuel cells containing hollow alloy particles, wherein the heat treatment step is performed at 60 to 80 ° C. for 1 to 2 hours.
상기 (3) 단계에서는,
상기 제2용액은 염기를 첨가하여 pH를 9∼12로 조절하는 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 1,
In step (3) above,
A method for producing a catalyst for fuel cells containing hollow alloy particles, characterized in that the pH of the second solution is adjusted to 9 to 12 by adding a base.
상기 염기는 수산화나트륨 또는 수산화칼륨인 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to clause 9,
A method for producing a catalyst for a fuel cell containing hollow alloy particles, wherein the base is sodium hydroxide or potassium hydroxide.
상기 (5) 단계에서는,
상기 산은 염산, 황산, 질산, 불산, 옥살산, 아세트산 및 글리콜산으로 이루어진 군에서 선택된 1종 이상인 것을 특징으로 하는 중공형 합금입자를 포함하는 연료전지용 촉매의 제조방법.According to claim 1,
In step (5) above,
A method for producing a catalyst for a fuel cell containing hollow alloy particles, wherein the acid is at least one selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, oxalic acid, acetic acid and glycolic acid.
상기 촉매는 복수 개의 중공형 합금입자로 이루어져 있고,
상기 합금입자는 Pt 및 1종 이상의 전이금속과의 합금인 것을 특징으로 하는 연료전지용 촉매.According to claim 12,
The catalyst consists of a plurality of hollow alloy particles,
A catalyst for fuel cells, wherein the alloy particles are an alloy of Pt and one or more transition metals.
상기 전이금속은 Ni, Co, Fe, Cr, Cu, Ru, Pd, Sn, V, Mo, W, 및 Ir로 이루어진 군에서 선택된 1종 이상인 것을 특징으로 하는 연료전지용 촉매.According to claim 13,
A catalyst for fuel cells, wherein the transition metal is one or more selected from the group consisting of Ni, Co, Fe, Cr, Cu, Ru, Pd, Sn, V, Mo, W, and Ir.
상기 중공형 합금입자의 입자간 평균 거리는 0.2 내지 0.25 nm인 것을 특징으로 하는 연료전지용 촉매.According to claim 13,
A catalyst for fuel cells, characterized in that the average distance between particles of the hollow alloy particles is 0.2 to 0.25 nm.
상기 촉매의 평균 입경은 9 내지 15 nm인 것을 특징으로 하는 연료전지용 촉매.According to claim 13,
A catalyst for fuel cells, characterized in that the average particle diameter of the catalyst is 9 to 15 nm.
A fuel cell containing the fuel cell catalyst according to claim 12.
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