JP5400924B2 - Method for producing gold-supported carbon catalyst - Google Patents
Method for producing gold-supported carbon catalyst Download PDFInfo
- Publication number
- JP5400924B2 JP5400924B2 JP2012129429A JP2012129429A JP5400924B2 JP 5400924 B2 JP5400924 B2 JP 5400924B2 JP 2012129429 A JP2012129429 A JP 2012129429A JP 2012129429 A JP2012129429 A JP 2012129429A JP 5400924 B2 JP5400924 B2 JP 5400924B2
- Authority
- JP
- Japan
- Prior art keywords
- gold
- liquid
- catalyst
- particles
- carbon catalyst
- 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.)
- Active
Links
- 239000003054 catalyst Substances 0.000 title claims description 68
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims description 46
- 229910052799 carbon Inorganic materials 0.000 title claims description 41
- 238000004519 manufacturing process Methods 0.000 title claims description 21
- 239000002245 particle Substances 0.000 claims description 107
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 106
- 239000010931 gold Substances 0.000 claims description 105
- 229910052737 gold Inorganic materials 0.000 claims description 105
- 239000007788 liquid Substances 0.000 claims description 70
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 15
- 230000003068 static effect Effects 0.000 claims description 14
- 230000002776 aggregation Effects 0.000 claims description 12
- 238000004220 aggregation Methods 0.000 claims description 11
- 239000003638 chemical reducing agent Substances 0.000 claims description 11
- 239000003795 chemical substances by application Substances 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 claims description 6
- 239000003112 inhibitor Substances 0.000 claims description 6
- KRKNYBCHXYNGOX-UHFFFAOYSA-K Citrate Chemical compound [O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O KRKNYBCHXYNGOX-UHFFFAOYSA-K 0.000 claims description 5
- 229920002873 Polyethylenimine Polymers 0.000 claims description 3
- 229920002125 Sokalan® Polymers 0.000 claims description 3
- 229940072107 ascorbate Drugs 0.000 claims description 3
- 239000011668 ascorbic acid Substances 0.000 claims description 3
- 235000010323 ascorbic acid Nutrition 0.000 claims description 3
- 239000004584 polyacrylic acid Substances 0.000 claims description 3
- 229920000036 polyvinylpyrrolidone Polymers 0.000 claims description 3
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 3
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims description 3
- QEMXHQIAXOOASZ-UHFFFAOYSA-N tetramethylammonium Chemical compound C[N+](C)(C)C QEMXHQIAXOOASZ-UHFFFAOYSA-N 0.000 claims description 3
- JAJIPIAHCFBEPI-UHFFFAOYSA-N 9,10-dioxoanthracene-1-sulfonic acid Chemical compound O=C1C2=CC=CC=C2C(=O)C2=C1C=CC=C2S(=O)(=O)O JAJIPIAHCFBEPI-UHFFFAOYSA-N 0.000 claims 3
- 239000003006 anti-agglomeration agent Substances 0.000 claims 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 68
- 229910052697 platinum Inorganic materials 0.000 description 34
- 239000000446 fuel Substances 0.000 description 15
- 238000006243 chemical reaction Methods 0.000 description 13
- 230000000052 comparative effect Effects 0.000 description 12
- 238000006722 reduction reaction Methods 0.000 description 12
- 239000000243 solution Substances 0.000 description 11
- 239000012279 sodium borohydride Substances 0.000 description 10
- 229910000033 sodium borohydride Inorganic materials 0.000 description 10
- 230000003197 catalytic effect Effects 0.000 description 9
- 229910052739 hydrogen Inorganic materials 0.000 description 8
- 239000001257 hydrogen Substances 0.000 description 8
- 229910052751 metal Inorganic materials 0.000 description 8
- 239000002184 metal Substances 0.000 description 8
- SDKPSXWGRWWLKR-UHFFFAOYSA-M sodium;9,10-dioxoanthracene-1-sulfonate Chemical compound [Na+].O=C1C2=CC=CC=C2C(=O)C2=C1C=CC=C2S(=O)(=O)[O-] SDKPSXWGRWWLKR-UHFFFAOYSA-M 0.000 description 8
- 229920000642 polymer Polymers 0.000 description 7
- 239000007787 solid Substances 0.000 description 7
- 238000003756 stirring Methods 0.000 description 7
- 230000002744 anti-aggregatory effect Effects 0.000 description 6
- 150000002431 hydrogen Chemical class 0.000 description 6
- 238000011068 loading method Methods 0.000 description 6
- 238000005259 measurement Methods 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 238000009826 distribution Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 239000001509 sodium citrate Substances 0.000 description 5
- HRXKRNGNAMMEHJ-UHFFFAOYSA-K trisodium citrate Chemical compound [Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O HRXKRNGNAMMEHJ-UHFFFAOYSA-K 0.000 description 5
- 229940038773 trisodium citrate Drugs 0.000 description 5
- 230000010718 Oxidation Activity Effects 0.000 description 4
- 239000002253 acid Substances 0.000 description 4
- 239000011162 core material Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 239000011148 porous material Substances 0.000 description 4
- 238000011946 reduction process Methods 0.000 description 4
- 239000011258 core-shell material Substances 0.000 description 3
- 239000010419 fine particle Substances 0.000 description 3
- 239000011259 mixed solution Substances 0.000 description 3
- 239000002105 nanoparticle Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 2
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000012670 alkaline solution Substances 0.000 description 2
- 229960004106 citric acid Drugs 0.000 description 2
- 235000015165 citric acid Nutrition 0.000 description 2
- 150000001860 citric acid derivatives Chemical class 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000706 filtrate Substances 0.000 description 2
- 239000003456 ion exchange resin Substances 0.000 description 2
- 229920003303 ion-exchange polymer Polymers 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000005518 polymer electrolyte Substances 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 239000012266 salt solution Substances 0.000 description 2
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000000967 suction filtration Methods 0.000 description 2
- 235000019263 trisodium citrate Nutrition 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 229920000557 Nafion® Polymers 0.000 description 1
- 239000004280 Sodium formate Substances 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 239000003929 acidic solution Substances 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 239000007771 core particle Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 210000003298 dental enamel Anatomy 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000003487 electrochemical reaction Methods 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 239000008151 electrolyte solution Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 150000002343 gold Chemical class 0.000 description 1
- FDWREHZXQUYJFJ-UHFFFAOYSA-M gold monochloride Chemical compound [Cl-].[Au+] FDWREHZXQUYJFJ-UHFFFAOYSA-M 0.000 description 1
- RJHLTVSLYWWTEF-UHFFFAOYSA-K gold trichloride Chemical class Cl[Au](Cl)Cl RJHLTVSLYWWTEF-UHFFFAOYSA-K 0.000 description 1
- 238000011005 laboratory method Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 150000003057 platinum Chemical class 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000000634 powder X-ray diffraction Methods 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 1
- 239000003223 protective agent Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- HLBBKKJFGFRGMU-UHFFFAOYSA-M sodium formate Chemical compound [Na+].[O-]C=O HLBBKKJFGFRGMU-UHFFFAOYSA-M 0.000 description 1
- 235000019254 sodium formate Nutrition 0.000 description 1
- ZWZLRIBPAZENFK-UHFFFAOYSA-J sodium;gold(3+);disulfite Chemical compound [Na+].[Au+3].[O-]S([O-])=O.[O-]S([O-])=O ZWZLRIBPAZENFK-UHFFFAOYSA-J 0.000 description 1
- 238000001694 spray drying Methods 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/0072—Preparation of particles, e.g. dispersion of droplets in an oil bath
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
- B01J21/18—Carbon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/48—Silver or gold
- B01J23/52—Gold
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/20—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state
- B01J35/23—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state in a colloidal state
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
- B01J35/391—Physical properties of the active metal ingredient
- B01J35/393—Metal or metal oxide crystallite size
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/40—Catalysts, in general, characterised by their form or physical properties characterised by dimensions, e.g. grain size
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
- B01J37/0018—Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat)
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/03—Precipitation; Co-precipitation
- B01J37/031—Precipitation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/16—Reducing
-
- 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
- H01M4/88—Processes of manufacture
- H01M4/8825—Methods for deposition of the catalytic active composition
- H01M4/8842—Coating using a catalyst salt precursor in solution followed by evaporation and reduction of the precursor
-
- 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
- H01M4/9041—Metals or alloys
- H01M4/905—Metals or alloys specially used in fuel cell operating at high temperature, e.g. SOFC
- H01M4/9058—Metals or alloys specially used in fuel cell operating at high temperature, e.g. SOFC of noble metals or noble-metal based alloys
-
- 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
- H01M4/9075—Catalytic material supported on carriers, e.g. powder carriers
- H01M4/9083—Catalytic material 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
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Electrochemistry (AREA)
- Dispersion Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Manufacturing & Machinery (AREA)
- Catalysts (AREA)
- Inert Electrodes (AREA)
- Fuel Cell (AREA)
Description
本発明は、金担持カーボン触媒及びその製造方法に関する。特に、固体高分子形の燃料電池用途に好適であり、白金使用量の低減に寄与する金担持カーボン触媒を提供する。 The present invention relates to a gold-supported carbon catalyst and a method for producing the same. In particular, the present invention provides a gold-supported carbon catalyst that is suitable for solid polymer fuel cell applications and contributes to a reduction in the amount of platinum used.
燃料電池は、次世代の発電システムとして期待が高く、特に固体高分子を電解質として用いる固体高分子形の燃料電池は、リン酸形燃料電池等と比較して動作温度が低く、かつコンパクトなため、電気自動車用の電源として利用が望まれている。 Fuel cells are highly expected as next-generation power generation systems. Solid polymer fuel cells that use solid polymers as electrolytes are particularly low in operating temperature and compact compared to phosphoric acid fuel cells. It is desired to be used as a power source for electric vehicles.
これら固体高分子形燃料電池には、電極として、電気化学的反応を促進させるための触媒と固体高分子との混合体が使用されている。そして、電極に用いられる触媒として、カーボン粉末等の導電性物質に、触媒成分として白金を担持させたものが一般的に知られている。白金を用いた触媒は、触媒能が高く、広い電位範囲で安定的に作用するためである。 In these solid polymer fuel cells, a mixture of a catalyst for promoting an electrochemical reaction and a solid polymer is used as an electrode. As a catalyst used for an electrode, a catalyst in which platinum is supported as a catalyst component on a conductive material such as carbon powder is generally known. This is because a catalyst using platinum has high catalytic ability and acts stably in a wide potential range.
しかしながら、白金は貴金属の中でも特に高価であり、燃料電池のコスト高の要因となることから、白金の使用量を低減した触媒の開発が求められている。特許文献1には、安価な金属酸化物等を用いることで、白金使用量を低減させた触媒が記載されており、特許文献2には、カーボン粉末の微細孔径よりも白金粒子の平均粒径を大きなものとすることで、微細構内へ白金粒子が入り込むことを防止し、白金の利用効率を向上する技術が記載されている。 However, platinum is particularly expensive among noble metals, and causes a high cost of the fuel cell. Therefore, development of a catalyst that reduces the amount of platinum used is required. Patent Document 1 describes a catalyst in which the amount of platinum used is reduced by using an inexpensive metal oxide, and Patent Document 2 describes the average particle diameter of platinum particles rather than the fine pore diameter of carbon powder. A technique for preventing the platinum particles from entering the fine premises and improving the utilization efficiency of platinum is described.
上記先行技術記載の触媒によれば、白金の使用量は低減できるものの、白金のみを用いた触媒と比較すると、実際に燃料電池の電極として使用した場合に触媒能が低いことや、耐久性に劣ることがあった。このため本発明は、固体高分子形燃料電池に好適な触媒において、白金の使用量を低減しつつ、白金のみを用いた場合と同様の触媒能や耐久性を実現可能な触媒の提供を目的とする。 According to the catalyst described in the above prior art, although the amount of platinum used can be reduced, compared with a catalyst using only platinum, when used as an electrode of a fuel cell, the catalytic ability is low, and durability is improved. It was inferior. Therefore, the present invention aims to provide a catalyst suitable for a polymer electrolyte fuel cell, which can realize the same catalytic ability and durability as when only platinum is used while reducing the amount of platinum used. And
上記課題を解決する触媒として、本発明者等は、白金触媒のための前駆材料として、カーボン担体に金粒子を担持させた金担持カーボン触媒を適用し、その金粒子上に白金粒子を積層させた2層構造とすることで、白金の使用量を低減できることに着目した。そして、かかる金担持触媒の物性について鋭意検討し、白金粒子のみを担持した触媒と同様の触媒能を実現するために、最適となる金粒子の形態を見出し本発明に想到するに至った。 As a catalyst for solving the above problems, the present inventors applied a gold-supported carbon catalyst in which gold particles are supported on a carbon support as a precursor material for the platinum catalyst, and laminated the platinum particles on the gold particles. We paid attention to the fact that the amount of platinum used can be reduced by using a two-layer structure. The inventors have diligently studied the physical properties of the gold-supported catalyst, and have found the optimal form of the gold particles to arrive at the present invention in order to realize the same catalytic ability as the catalyst supporting only platinum particles.
すなわち本発明は、担体であるカーボンに金粒子が担持された触媒において、金粒子は、平均粒径2.0nm〜6.0nmであり、粒径の標準偏差が30%以内である金担持カーボン触媒に関する。このように微細且つ粒径分布がシャープなバラツキの少ない金粒子を担持した触媒によれば、白金粒子のみを担持した触媒と同様の触媒能としつつ、白金の使用量を低減することが可能となる。 That is, the present invention relates to a catalyst in which gold particles are supported on carbon as a carrier, wherein the gold particles have an average particle diameter of 2.0 nm to 6.0 nm and a standard deviation of the particle diameter is within 30%. Relates to the catalyst. In this way, according to the catalyst supporting gold particles having a fine particle size distribution with little variation, it is possible to reduce the amount of platinum used while having the same catalytic ability as a catalyst supporting only platinum particles. Become.
本発明の触媒において、担体に担持された金粒子は、平均粒径2.0nm〜6.0nmの範囲内であり、コアシェル触媒のコア材として平均粒径は3.0nm〜5.0nmであるとより好ましい。2.0nm未満であると、金粒子上に白金を積層した際に、酸性雰囲気下で白金が溶出する可能性がある。6.0nmを超えると、反応場としての表面積が稼げず、触媒能が低下しやすい。また、金粒子の粒径は、標準偏差30%以内である。標準偏差30%を超えると、粒子径の偏った状態になるため、その後金粒子上に白金粒子を析出させた際に安定した性能を得られない可能性がある。尚、平均粒径の算出法としてはX線回折によるのが簡便である。また、粒径の標準偏差の算出としては、透過型電子顕微鏡(TEM)による写真(好ましくは、3〜5枚の複数を使用)から、任意個数(好ましくは、200〜300個)の粒子を抽出して粒径を測定して求めることができる。 In the catalyst of the present invention, the gold particles supported on the carrier have an average particle diameter in the range of 2.0 nm to 6.0 nm, and the average particle diameter is 3.0 nm to 5.0 nm as the core material of the core-shell catalyst. And more preferred. If the thickness is less than 2.0 nm, platinum may be eluted in an acidic atmosphere when platinum is laminated on the gold particles. If it exceeds 6.0 nm, the surface area as a reaction field cannot be obtained, and the catalytic ability tends to decrease. The particle size of the gold particles is within 30% of standard deviation. If the standard deviation exceeds 30%, the particle diameter is in a biased state, and there is a possibility that stable performance cannot be obtained when platinum particles are subsequently deposited on the gold particles. It is easy to calculate the average particle diameter by X-ray diffraction. In calculating the standard deviation of the particle size, an arbitrary number of particles (preferably 200 to 300 particles) is taken from a photograph (preferably using a plurality of 3 to 5 pieces) by a transmission electron microscope (TEM). It can be determined by extracting and measuring the particle size.
本発明の金担持触媒は、金粒子上に白金粒子を析出させた触媒とすることにより、固体高分子形の燃料電池用コアシェル触媒としても利用可能となる。この金担持触媒の金の担持率は10〜70%が望ましく、より好ましいのは20〜60%である。金の担持率が10%以下だと、白金の析出する反応場がなくなってしまい、70%以上だと金粒子同士が凝集してしまうため、コア材としての機能がなくなってしまう。上記の範囲内であれば、白金使用量を低減しつつ、触媒能及び耐久性が白金のみを担持した場合と同程度である触媒とみなすことができる。尚、本発明は、担体上の金粒子の平均粒径、粒径分布を適正化したことにより、上記の担持率とすることで、それ自体も触媒活性を有する。 The gold-supported catalyst of the present invention can be used as a core-shell catalyst for a solid polymer fuel cell by using a catalyst in which platinum particles are deposited on gold particles. The gold loading ratio of this gold-supported catalyst is preferably 10 to 70%, more preferably 20 to 60%. When the gold loading ratio is 10% or less, the reaction field where platinum is deposited disappears. When the gold loading ratio is 70% or more, the gold particles are aggregated, and the function as the core material is lost. If it is in said range, it can be considered that the catalyst capacity and durability are equivalent to the case where only platinum is carried, reducing the amount of platinum used. In addition, this invention itself has a catalyst activity by setting it as said loading rate by optimizing the average particle diameter and particle size distribution of the gold particle on a support | carrier.
次に、本発明の金担持カーボン触媒の製造方法について説明する。本発明の金担持カーボン触媒は、金塩の水溶液を還元処理して金粒子を析出させ、この反応液に担体を接触させて金粒子を担持する方法によるものが好ましい。本発明の金担持カーボン触媒は、微細な金粒子をカーボン担体表面に均一に分散担持したものであるが、担体の細孔内部にまで担持させるのが好ましい。この点、金粒子の担持形態としては、別途製造した粒子状態の金を担体に吸着担持する方法も考えられるが、このような別途製造した金粒子は、金粒子の安定性確保のための保護剤が必要となり、かかる保護剤を含む金粒子は担体の細孔に侵入し難い。本発明では、金塩溶液と還元剤とを混合して金を還元した直後の反応液に担体を接触させることで、金のみからなる微細粒子を細孔にまで侵入させ金粒子が均一に担持した金担持カーボン触媒とすることができる。 Next, the manufacturing method of the gold | metal | money carrying | support carbon catalyst of this invention is demonstrated. The gold-supported carbon catalyst of the present invention is preferably produced by a method in which an aqueous solution of gold salt is subjected to a reduction treatment to precipitate gold particles, and a carrier is brought into contact with this reaction solution to support the gold particles. The gold-supported carbon catalyst of the present invention is obtained by uniformly supporting fine gold particles on the surface of a carbon support, but it is preferable to support even inside the pores of the support. In this regard, as a form of supporting gold particles, a method of adsorbing and supporting separately produced gold particles on a carrier is also conceivable, but such separately manufactured gold particles are protected to ensure the stability of the gold particles. An agent is required, and gold particles containing such a protective agent are unlikely to enter the pores of the carrier. In the present invention, a gold salt solution and a reducing agent are mixed to bring the carrier into contact with the reaction solution immediately after reducing the gold, so that fine particles made only of gold can penetrate into the pores and the gold particles are uniformly supported. The gold-supported carbon catalyst can be obtained.
そして、本発明の金担持カーボン触媒を還元析出法により製造する場合、金の還元を、均一且つ適度な反応速度で進行させることが重要となる。本発明のように平均粒径2.0nm〜6.0nmという微細な金粒子とするには、その製造工程において、金粒子の凝集や沈殿が特に進行しやすく、特に還元工程において、微粒かつバラツキの少ない金粒子が形成しやすい条件とすることが必要になるためである。このような還元工程として例えば、反応溶液を高速で撹拌しながら反応させる方法等が考えられるが、かかる実験室的方法は工業的規模での生産に不適当といえる。 And when manufacturing the gold | metal | money carrying | support carbon catalyst of this invention by a reduction | restoration precipitation method, it is important to advance reduction | restoration of gold | metal | money at a uniform and moderate reaction rate. In order to obtain fine gold particles having an average particle diameter of 2.0 nm to 6.0 nm as in the present invention, the aggregation and precipitation of gold particles are particularly likely to proceed in the production process, and in particular in the reduction process, fine particles and variations. This is because it is necessary to make the conditions easy to form gold particles with a small amount. As such a reduction step, for example, a method of reacting the reaction solution while stirring at high speed can be considered, but such a laboratory method is inappropriate for production on an industrial scale.
本発明者等は、微細かつ粒径の揃った金粒子を確実にかつ効率的に製造することができる方法について鋭意検討した。その結果、金塩と凝集防止剤とを含むA液と、還元剤と凝集防止剤とを含むB液とを調整する工程と、調整したA液とB液とをスタティックミキサー中で反応させて金を還元させる工程と、金を還元させた後、A液とB液との混合液に担体であるカーボンを接触させて金を担持させる工程とを含む製造方法に想到した。以下、上記製造方法について詳細に説明する。 The inventors of the present invention diligently studied a method that can reliably and efficiently produce gold particles having a uniform particle size. As a result, the step of adjusting the liquid A containing the gold salt and the anti-aggregation agent, and the liquid B containing the reducing agent and the anti-aggregation agent, and the adjusted liquid A and B were reacted in a static mixer. The inventors have conceived a production method including a step of reducing gold and a step of supporting gold by bringing carbon as a carrier into contact with a mixed solution of the liquid A and the liquid B after reducing the gold. Hereafter, the said manufacturing method is demonstrated in detail.
まず、A液について説明する。金塩の種類としては、塩化金、塩化金酸、亜硫酸金ナトリウム等を適用できる。これら金塩の含有量は、A液中において、0.10〜0.80mMの範囲内とすることが好ましい。この範囲内であると、平均粒径2.0〜6.0nmで均一な金粒子を形成しやすいためである。0.10mM未満であると均一な金粒子を形成しにくく、0.80mMを超えると平均粒径6nm以下の金粒子とすることが困難な傾向となる。尚、A液には、溶媒として酸性溶液、アルカリ性溶液、または純水用いることができる。 First, A liquid is demonstrated. As the kind of gold salt, gold chloride, chloroauric acid, sodium gold sulfite and the like can be applied. The content of these gold salts is preferably in the range of 0.10 to 0.80 mM in the liquid A. This is because it is easy to form uniform gold particles having an average particle size of 2.0 to 6.0 nm within this range. If it is less than 0.10 mM, it is difficult to form uniform gold particles, and if it exceeds 0.80 mM, it tends to be difficult to obtain gold particles having an average particle diameter of 6 nm or less. In addition, an acidic solution, an alkaline solution, or pure water can be used for A liquid as a solvent.
A液には、金の凝集を防止して微細な金粒子を形成させるべく、凝集防止剤を含むものとしている。凝集防止剤としては、クエン酸やクエン酸三ナトリウム等のクエン酸塩の他、アスコルビン酸塩、ポリビニルピロリドン、ポリエチレンイミン、ポリアクリル酸、テトラメチルアンモニウムが適用できる。好ましいのはクエン酸、クエン酸塩である。凝集防止剤濃度は、金塩濃度に対してモル比で2〜15倍まで対応でき、より好ましいのは6〜12倍である。2倍未満であると、金粒子がカーボン上に吸着し難くなり、15倍を超えると、金粒子が粗大化する傾向となる。 The liquid A contains an agglomeration inhibitor in order to prevent gold aggregation and to form fine gold particles. As the aggregation inhibitor, citrates such as citric acid and trisodium citrate, ascorbate, polyvinylpyrrolidone, polyethyleneimine, polyacrylic acid, and tetramethylammonium can be applied. Preference is given to citric acid and citrate. The aggregation inhibitor concentration can correspond to a molar ratio of 2 to 15 times, more preferably 6 to 12 times the gold salt concentration. If it is less than 2 times, the gold particles are hardly adsorbed on the carbon, and if it exceeds 15 times, the gold particles tend to be coarse.
次に、B液について説明する。B液に含まれる還元剤としては、水素化ホウ素ナトリウム(SBH)、ヒドラジン、ギ酸ナトリウム、アルコール等を適用できるがSBHが好ましい。上記還元剤の含有量は、B液中において0.1〜5.0mMとする。0.1mM未満であると均一な金粒子を形成しにくく、5.0mMを超えると金粒子同士の凝集が起こりやすい。より好ましい条件は0.3〜3.0mMの範囲内である。尚、B液には、溶媒としてアルカリ溶液または純水を用いることができる。 Next, the B liquid will be described. As the reducing agent contained in the liquid B, sodium borohydride (SBH), hydrazine, sodium formate, alcohol, and the like can be applied, but SBH is preferable. Content of the said reducing agent shall be 0.1-5.0 mM in B liquid. If it is less than 0.1 mM, it is difficult to form uniform gold particles, and if it exceeds 5.0 mM, aggregation of gold particles tends to occur. More preferred conditions are in the range of 0.3 to 3.0 mM. In the liquid B, an alkaline solution or pure water can be used as a solvent.
本発明の金担持触媒の製造方法では、上記したA液のみならず、B液にも凝集防止剤を含むことを要する。B液も凝集防止剤を含むものとすることで、金の還元が均一且つ適度な反応速度で進行するものとなる。凝集防止剤としては、A液と同様、クエン酸、クエン酸三ナトリウム等のクエン酸塩の他、アスコルビン酸塩、ポリビニルピロリドン、ポリエチレンイミン、ポリアクリル酸、テトラメチルアンモニウム等が使用できる。好ましくは、クエン酸、クエン酸塩である。凝集防止剤モル濃度は、還元剤モル濃度に対してモル比で0.2〜1.5倍の範囲内であると好ましい。0.2倍未満であると金が還元されずに担体から脱落してしまい、1.5倍を超えると粒子の粗大化が起きてしまう。 In the method for producing a gold-supported catalyst of the present invention, it is necessary that not only the above-described A liquid but also the B liquid contain an aggregation inhibitor. Liquid B also contains an anti-aggregation agent, so that the reduction of gold proceeds at a uniform and moderate reaction rate. As an anti-aggregation agent, as in solution A, citrates such as citric acid and trisodium citrate, ascorbate, polyvinyl pyrrolidone, polyethyleneimine, polyacrylic acid, tetramethylammonium and the like can be used. Preferred are citric acid and citrate. The aggregation inhibitor molar concentration is preferably in the range of 0.2 to 1.5 times the molar ratio of the reducing agent molar concentration. If it is less than 0.2 times, gold falls off from the carrier without being reduced, and if it exceeds 1.5 times, the particles become coarse.
次に、以上説明したA液とB液とを混合し、金を還元させる工程について説明する。金の還元工程では、A液とB液との混合にスタティックミキサーを使用する。スタティックミキサーによれば、A液とB液とを、短時間で安定した高い均一度で混合可能となるため、少量ずつ速やかに金の還元反応を均一に進行させることができる。スタティックミキサーとしては、内部に導入するスタティックミキサーは6エレメント以上30エレメント以下のものを使用することが好ましい。上記エレメント数未満であると、A液とB液との混合が不十分かつ粒子径のばらつきが大きくなる傾向がある。また、上記エレメント数を超えてしまうと装置が大型化してしまう可能性がある。さらに好ましくは10エレメント以上25エレメント以下である。 Next, the process of mixing the A liquid and B liquid described above to reduce gold will be described. In the gold reduction process, a static mixer is used for mixing the A liquid and the B liquid. According to the static mixer, the liquid A and the liquid B can be mixed in a short time with a stable and high degree of uniformity, so that the reduction reaction of gold can be progressed uniformly little by little. As the static mixer, it is preferable to use a static mixer introduced in the interior of 6 to 30 elements. If the number of elements is less than the above, the mixing of the liquid A and the liquid B tends to be insufficient and the variation in the particle diameter tends to increase. Moreover, if the number of elements is exceeded, the apparatus may become large. More preferably, it is 10 elements or more and 25 elements or less.
以上の金の還元工程では、A液とB液(A液:B液)とを1:1〜1:5の流量割合で混合させることが好ましい。この範囲内であると、適度な反応速度で金の還元を進行させることができる。A液の送液量が多すぎると、平均粒径6.0nm以下の金粒子とすることが困難な傾向となり、B液の送液量が多すぎると、還元反応を均一に進行させることが困難な傾向となる。より好ましくは1:2〜1:3である。 In the gold reduction process described above, it is preferable to mix the liquid A and liquid B (liquid A: liquid B) at a flow rate ratio of 1: 1 to 1: 5. Within this range, the reduction of gold can proceed at an appropriate reaction rate. If the amount of liquid A is too large, it tends to be difficult to obtain gold particles having an average particle size of 6.0 nm or less. If the amount of liquid B is excessively large, the reduction reaction can proceed uniformly. It becomes a difficult tendency. More preferably, it is 1: 2 to 1: 3.
本発明の製造方法では、A液とB液とを混合して金の還元を進行させた溶液に、担体であるカーボンを後から接触させて金を担持させる。このように、先に金を還元させた後に担体に金を担持させることで、粒径の均一な金粒子を担体上に固定する。尚、混合液とカーボンとの接触は、混合液にカーボン分散液を投入して混合液をカーボンに含浸させるのが好ましい。 In the production method of the present invention, a carrier, carbon, is later brought into contact with a solution obtained by mixing the liquid A and the liquid B to promote reduction of gold, thereby supporting the gold. Thus, gold | metal | money with a uniform particle diameter is fixed on a support | carrier by carrying | supporting gold | metal | money on a support | carrier after reducing gold | metal | money previously. The contact between the mixed liquid and carbon is preferably performed by introducing a carbon dispersion into the mixed liquid and impregnating the mixed liquid with carbon.
本発明によれば、微細且つバラツキの少ない金粒子を担持した金担持カーボン触媒により、白金の使用量を低減しつつ、白金のみを用いた場合と同様の触媒能や耐久性を実現可能な燃料電池用触媒が提供可能となる。 According to the present invention, a fuel capable of realizing the same catalytic ability and durability as in the case of using only platinum while reducing the amount of platinum used by the gold-supported carbon catalyst supporting gold particles with fine and small variations. A battery catalyst can be provided.
本発明に係る金粒子を担持した触媒は、白金担持により燃料電池用触媒とすることができる。その際、本発明に係る触媒を塩化白金酸等の白金塩溶液に浸漬させて、金粒子上に白金粒子を析出させることにより、固体高分子形の燃料電池用触媒として利用可能となる。 The catalyst carrying gold particles according to the present invention can be used as a fuel cell catalyst by carrying platinum. At that time, the catalyst according to the present invention is immersed in a platinum salt solution such as chloroplatinic acid and the platinum particles are deposited on the gold particles, whereby the catalyst can be used as a solid polymer fuel cell catalyst.
以下、本発明における最良の実施形態について説明する。 Hereinafter, the best embodiment of the present invention will be described.
[第一実施形態]:ここでは、スタティックミキサーの使用有無、担体であるカーボンの添加順序を変化させて金担持触媒を製造し、得られた触媒の金粒子粒径等を測定した。 [First Embodiment]: Here, a gold-supported catalyst was produced by changing the use / non-use of a static mixer and the addition order of carbon as a carrier, and the gold particle size and the like of the obtained catalyst were measured.
実施例1
(各混合液の調製)
純水5Lをケミカルミキサーで撹拌しながら金含有量48%の塩化金酸0.61gと、純度99%のクエン酸三ナトリウム2水和物2.5gとを添加し、塩化金塩0.29mM、クエン酸三ナトリウム1.70mM(0.05wt%)を含むA液を調整した。同様に、純水15Lを撹拌しながら純度92%の水素化ホウ素ナトリウム(SBH)0.51gと、純度99%のクエン酸三ナトリウム2水和物2.5gとを添加し、SBH0.83mM、クエン酸三ナトリウム0.57mM(0.02wt%)を含むB液を調整した。
Example 1
(Preparation of each mixture)
While stirring 5 L of pure water with a chemical mixer, 0.61 g of chloroauric acid with a gold content of 48% and 2.5 g of trisodium citrate dihydrate with a purity of 99% were added, and the gold chloride salt was 0.29 mM. A solution containing 1.70 mM (0.05 wt%) trisodium citrate was prepared. Similarly, 0.51 g of 92% purity sodium borohydride (SBH) and 2.5 g of 99% purity trisodium citrate dihydrate were added while stirring 15 L of pure water, and SBH 0.83 mM, A solution B containing 0.57 mM (0.02 wt%) trisodium citrate was prepared.
(金粒子液の合成とカーボンへの担持)
調整したA液及びB液を、A液500mL/min、B液1000mL/minの流量として(A液:B液=1:2)、長さ13.5cm(エレメント数:20個)のスタティックミキサーにて混合して金を還元させた。混合液は20Lのホーロー製タンクで受け、タンク内の溶液は攪拌機(攪拌速度200rpm)により、攪拌を行った。尚、反応温度は25℃とした。混合後の溶液に、カーボン担体(ケッチェンブラックEC 比表面積800m2/g)0.43g添加して約3時間反応させ金粒子をカーボン担体上に担持させた。その後、吸引濾過を行い、純水ベッセル洗浄を3回行った後に60℃の大気圧乾燥機にて一昼乾燥させて金担持カーボン触媒を得た。
(Synthesis of gold particle liquid and loading on carbon)
The adjusted A liquid and B liquid were flow mixers A liquid 500 mL / min, B liquid 1000 mL / min (A liquid: B liquid = 1: 2), 13.5 cm long (number of elements: 20) static mixer To reduce the gold. The liquid mixture was received in a 20 L enamel tank, and the solution in the tank was stirred with a stirrer (stirring speed 200 rpm). The reaction temperature was 25 ° C. To the mixed solution, 0.43 g of carbon support (Ketjen Black EC specific surface area 800 m 2 / g) was added and reacted for about 3 hours to support the gold particles on the carbon support. Thereafter, suction filtration was performed, and pure water vessel washing was performed three times, followed by drying for one day in an atmospheric pressure dryer at 60 ° C. to obtain a gold-supported carbon catalyst.
比較例1
A液とB液を、スタティックミキサーを利用した反応系を使わず、ケミカルミキサー(攪拌速度800rpm)を用いて混合したことを除き、実施例1と同様の製造方法で触媒を製造した。
Comparative Example 1
A catalyst was produced by the same production method as in Example 1 except that the liquid A and the liquid B were mixed using a chemical mixer (stirring speed: 800 rpm) without using a reaction system using a static mixer.
比較例2
A液とB液を、スタティックミキサーを利用した反応系を使わず、ケミカルミキサー(攪拌速度300rpm)を用いて混合したことを除き、実施例1と同様の製造方法で触媒を製造した。
Comparative Example 2
A catalyst was produced by the same production method as in Example 1 except that the liquid A and the liquid B were mixed using a chemical mixer (stirring speed: 300 rpm) without using a reaction system using a static mixer.
比較例3
金の還元前にカーボン粉末を添加した。あらかじめA液とB液の混合液を受ける容器部分にコロイドミルを用いて高分散させたカーボン液添加してから、スタティックミキサーにてA液とB液と混合したこと以外、実施例1と同様の製造方法で触媒を製造した。
Comparative Example 3
Carbon powder was added before gold reduction. The same as in Example 1, except that the carbon liquid that was highly dispersed using a colloid mill was added to the container portion that previously received the liquid mixture of liquid A and liquid B, and then mixed with liquid A and liquid B using a static mixer. The catalyst was manufactured by the manufacturing method of.
以上の実施例及び比較例で得られた触媒について、粉末X線回折測定を行い、ピークの回折角及びその半値幅からシェラーの式より平均粒径を算出した。また、TEM観察(加速電圧200KeV、倍率20万倍)を行い、撮影した5枚の写真から300個の粒子を抽出して粒径の標準偏差を算出した。これらの結果を以下の表に示す。 The catalysts obtained in the above Examples and Comparative Examples were subjected to powder X-ray diffraction measurement, and the average particle diameter was calculated from Scherrer's equation from the peak diffraction angle and its half width. Further, TEM observation (acceleration voltage 200 KeV, magnification 200,000 times) was performed, 300 particles were extracted from the five photographs taken, and the standard deviation of the particle diameter was calculated. These results are shown in the table below.
表1より、スタティックミキサーを使用しない比較例1及び比較例2では実施例1よりも平均粒子径が1〜2nm程度大きくなった。これは、実施例1において反応系をスタティックミキサーの反応管内という狭い反応場内で金還元工程を制限し、且つスタティックミキサーのエレメント数を適正にすることによって金粒子生成時の攪拌効率を向上させたことにより、金粒子の小粒径化を図ることができたものと考えられる。 From Table 1, in Comparative Example 1 and Comparative Example 2 in which no static mixer was used, the average particle size was about 1 to 2 nm larger than that in Example 1. This limited the gold reduction process in the narrow reaction field of the reaction tube of the static mixer in Example 1, and improved the stirring efficiency at the time of generating gold particles by making the number of elements of the static mixer appropriate. Thus, it is considered that the gold particles can be reduced in size.
また、比較例3では実施例1よりも平均粒径が10nm程度粗大化している。これは、金粒子が熟成しきらないうちに(還元された金粒子が安定しないうちに)、カーボン上に担持されるため、カーボン表面上での金粒子が凝集、粗大化してしまうためであると考えられる。したがって、カーボンを投入するタイミングはA液とB液を完全に混合し終わった後に、添加することが望ましいと考えられる。 Further, in Comparative Example 3, the average particle size is coarsened by about 10 nm compared to Example 1. This is because the gold particles are agglomerated and coarsened on the carbon surface because they are supported on the carbon before the gold particles are fully aged (before the reduced gold particles are stable). it is conceivable that. Therefore, it is considered desirable to add the carbon after the liquid A and the liquid B are completely mixed.
図1は実施例1で合成した金ナノ粒子の電子顕微鏡像である。金粒子は2.5〜5.0nm程度の状態で多く存在している。また、実施例1についてTEM観察により粒径分布を測定したところ、図2のようになった。この結果から、この製法で合成した金粒子は2.5〜5.0nmの状態で多く存在しており、コアシェル触媒のコア材としては適正な粒径の範囲内であるといえる。 FIG. 1 is an electron microscopic image of the gold nanoparticles synthesized in Example 1. Many gold particles are present in a state of about 2.5 to 5.0 nm. Further, when the particle size distribution of Example 1 was measured by TEM observation, it was as shown in FIG. From this result, it can be said that many gold particles synthesized by this production method are present in a state of 2.5 to 5.0 nm, and are within the range of the appropriate particle size as the core material of the core-shell catalyst.
[第二実施形態]
ここでは、金塩濃度、還元剤濃度、凝集防止剤濃度を変化させて触媒を製造し、得られた触媒の平均粒径及び標準偏差を比較した。
[Second Embodiment]
Here, the catalyst was produced by changing the gold salt concentration, the reducing agent concentration, and the aggregation preventing agent concentration, and the average particle diameter and standard deviation of the obtained catalysts were compared.
実施例2〜5、比較例4
塩化金酸の添加量を調整し、濃度0.18〜0.88mMの金塩を含むA液を調製した。A液中の金濃度以外、及びB液の組成条件は、実施例1と同様とした。結果を以下の表に示す。
Examples 2 to 5 and Comparative Example 4
The amount of chloroauric acid added was adjusted to prepare solution A containing gold salt with a concentration of 0.18 to 0.88 mM. Except for the gold concentration in the liquid A, the composition conditions of the liquid B were the same as in Example 1. The results are shown in the table below.
表2の結果より金濃度が高いほど、金の平均粒径は大きくなる。比較例4において粒子径は6.1nmとなり金コア粒子として望ましい平均粒径の範囲を僅かに超えてしまう。そのため、平均粒径は3.0〜5.0nmという、コア材として好ましい金の粒子径を作成するためには実施例1〜5の金濃度範囲が適している。 From the results in Table 2, the higher the gold concentration, the larger the average gold particle size. In Comparative Example 4, the particle diameter is 6.1 nm, which is slightly beyond the range of the average particle diameter desirable for gold core particles. Therefore, the gold concentration range of Examples 1 to 5 is suitable for preparing a gold particle size that is 3.0 to 5.0 nm and that is preferable as a core material.
実施例6〜9
B液における水素化ホウ素ナトリウム(SBH)の添加量を0.10〜1.53gとして、濃度0.18〜2.70mMの還元剤を含むB液を調整した。水素化ホウ素ナトリウム以外の条件は、実施例1と同様とした。結果を以下の表に示す。
Examples 6-9
Liquid B containing a reducing agent having a concentration of 0.18 to 2.70 mM was prepared by setting the amount of sodium borohydride (SBH) added in liquid B to 0.10 to 1.53 g. Conditions other than sodium borohydride were the same as in Example 1. The results are shown in the table below.
表3の結果から、実施例6のように金濃度に対するSBH量が少なくなると、粒子径が大きくなる傾向がわかる。これは、金粒子が一部未還元の状態で存在し、未還元粒子同士が凝集して粗大化するためと考えられる。実際に、金の還元率は実施例7〜9においては金投入量の98%以上であるのに対し、実施例6では95%とわずかに低くなっていた。そのため還元剤の投入量は0.3mM以上が好ましい。 From the results in Table 3, it can be seen that when the amount of SBH relative to the gold concentration decreases as in Example 6, the particle diameter tends to increase. This is presumably because some of the gold particles are present in an unreduced state, and the unreduced particles are aggregated and coarsened. Actually, the reduction rate of gold was 98% or more of the amount of gold input in Examples 7 to 9, whereas it was slightly low at 95% in Example 6. Therefore, the input amount of the reducing agent is preferably 0.3 mM or more.
実施例10〜13
凝集防止剤であるクエン酸三ナトリウムの添加量を調整し、金塩モル濃度に対して2〜12倍の凝集防止剤を含むA液を調整した。それ以外の条件は、実施例1と同様とした。また、ここでは、金粒子をカーボン担体上に担持させた後の吸引濾過の際、濾液への金溶出量も測定した。この結果を以下の表に示す。
Examples 10-13
The amount of trisodium citrate, which is an anti-aggregation agent, was adjusted to prepare solution A containing 2 to 12 times the anti-aggregation agent relative to the gold salt molar concentration. The other conditions were the same as in Example 1. Here, the amount of gold eluted into the filtrate was also measured during suction filtration after the gold particles were supported on the carbon support. The results are shown in the following table.
表4の結果から、金に対するクエン酸塩の投入量が多いほど、平均粒子径も大きくなる傾向が見られる。また、クエン酸塩の投入量が少なくなると担持直後の濾過を行った際に濾液への金の溶出が見られた。そのため、3nm前後の粒子を作るためには実施例11の形態がもっとも好ましいといえる。 From the results in Table 4, it can be seen that the larger the amount of citrate added to gold, the larger the average particle size. In addition, when the amount of citrate was decreased, gold was eluted into the filtrate when filtration was performed immediately after loading. Therefore, it can be said that the form of Example 11 is most preferable for producing particles of around 3 nm.
[第三実施形態]
実施例1の金担持触媒について実際に電極を作成し水素酸化活性について測定をおこなった。測定用電極の作製および測定は以下の手順で行った。また、比較対象として、比較例1の平均金粒子径が4.5nmの金/カーボンを作成し、同様に電極を作成・評価した。
[Third embodiment]
An electrode was actually prepared for the gold-supported catalyst of Example 1, and the hydrogen oxidation activity was measured. The measurement electrode was produced and measured in the following procedure. Further, as a comparison object, gold / carbon having an average gold particle diameter of 4.5 nm in Comparative Example 1 was prepared, and electrodes were similarly prepared and evaluated.
(電極製作)
イオン交換樹脂(商品名:ナフィオン(登録商標)、Dupont社製)の5%溶液をスプレードライにより製造した樹脂粉末1.2gに触媒をカーボン粉末基準で1g秤量して混合し、これらを1−プロパノールと水との混合溶液25mLに入れ、これをボールミルにて50分間混合させて触媒ペーストとした。そして、カーボンとイオン交換樹脂とが表層にコーティングされたPTFEを含浸したカーボンペーパーをガス拡散層として、これに前記触媒ペーストを金量が0.56mg/cm2となるように塗布印刷した。更に、これを60℃で乾燥させた後、130℃、20kg/cm2で1分間ホットプレスして電極とした。
(性能測定)
上記で製作した電極の特性は、次のように測定した。作製した電極を用いて半電池(ハーフセル)を製造した。ここでは、硫酸を電解液とし、対極として白金メッシュを用い、参照極として標準水素電極を用い、作製した電極を作用極としてこれに燃料を供給して電流を流し、電流密度500mA/cm2における分極値(水素の酸化活性過電圧)を測定した。試験条件は以下の通りである。
電極面積:7cm2
温度:60℃
燃料:100%水素
(Electrode production)
1 g of a catalyst based on carbon powder is weighed and mixed with 1.2 g of a resin powder produced by spray drying a 5% solution of an ion exchange resin (trade name: Nafion (registered trademark), manufactured by Dupont). This was put in 25 mL of a mixed solution of propanol and water, and mixed with a ball mill for 50 minutes to obtain a catalyst paste. Then, carbon paper impregnated with PTFE having carbon and an ion exchange resin coated on the surface layer was used as a gas diffusion layer, and the catalyst paste was applied and printed on the carbon paste so that the gold amount was 0.56 mg / cm 2 . Furthermore, after drying this at 60 degreeC, it hot-pressed for 1 minute at 130 degreeC and 20 kg / cm < 2 >, and was set as the electrode.
(Performance measurement)
The characteristics of the electrode manufactured above were measured as follows. A half battery (half cell) was produced using the produced electrode. Here, the sulfuric acid and the electrolytic solution, a platinum mesh as a counter electrode, using a standard hydrogen electrode as a reference electrode, electric current is supplied to the fuel to the electrode prepared as a working electrode, at a current density of 500mA / cm 2 The polarization value (hydrogen oxidation active overvoltage) was measured. The test conditions are as follows.
Electrode area: 7 cm 2
Temperature: 60 ° C
Fuel: 100% hydrogen
図3は、水素酸化活性の測定結果である。この結果から、実施例1の方が比較例1と比較して高電密・低電圧を達成できている。つまり同じ金担持率ならば金の粒子が小さいほど金属表面積=水素酸化の反応場が広いために水素酸化活性が高いことが分かった。このように、金粒子の粒径、粒径分布の適正化は活性改善に有効であることが確認され、かかる金担持触媒に白金を担持することで、有効な触媒活性を得ることができると考えられる。 FIG. 3 shows the measurement results of hydrogen oxidation activity. From this result, compared with Comparative Example 1, Example 1 can achieve higher electrical density and lower voltage. In other words, it was found that the smaller the gold particles, the higher the hydrogen oxidation activity because the smaller the gold particles, the wider the metal surface area = the hydrogen oxidation reaction field. As described above, it is confirmed that the optimization of the particle size and particle size distribution of the gold particles is effective in improving the activity, and by supporting platinum on the gold-supported catalyst, effective catalytic activity can be obtained. Conceivable.
本発明の金担持カーボン触媒によれば、白金使用量を低減しつつ、白金のみを用いた触媒と同様の触媒性能を維持可能な固体高分子形の燃料電池用触媒を提供可能となる。 According to the gold-supported carbon catalyst of the present invention, it is possible to provide a polymer electrolyte fuel cell catalyst capable of maintaining the same catalytic performance as a catalyst using only platinum while reducing the amount of platinum used.
Claims (5)
金塩と凝集防止剤を含むA液と、還元剤と凝集防止剤を含むB液とを用意する工程と、
調整したA液とB液とをスタティックミキサー中で反応させて金を還元させる工程と、
金を還元させた後、A液とB液との混合液に担体であるカーボンを接触させて金を担持させる工程を含む金担持カーボン触媒の製造方法。 It is a method for producing a gold-supported carbon catalyst in which gold particles are supported on carbon as a carrier, and the gold particles have an average particle diameter of 2.0 nm to 6.0 nm and a standard deviation of the particle diameter is within 30%. ,
Preparing a liquid A containing gold salt and an anti-agglomeration agent, and a liquid B containing a reducing agent and an anti-agglomeration agent;
Reacting the adjusted liquid A and liquid B in a static mixer to reduce gold;
A method for producing a gold-supported carbon catalyst, comprising a step of bringing gold as a carrier into contact with a mixed liquid of liquid A and liquid B after reducing gold.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2012129429A JP5400924B2 (en) | 2012-06-07 | 2012-06-07 | Method for producing gold-supported carbon catalyst |
TW102120076A TWI508774B (en) | 2012-06-07 | 2013-06-06 | Production method for gold-supported carbon catalyst |
PCT/JP2013/065683 WO2013183704A1 (en) | 2012-06-07 | 2013-06-06 | Gold-loaded carbon catalyst and method for producing same |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2012129429A JP5400924B2 (en) | 2012-06-07 | 2012-06-07 | Method for producing gold-supported carbon catalyst |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2013252483A JP2013252483A (en) | 2013-12-19 |
JP5400924B2 true JP5400924B2 (en) | 2014-01-29 |
Family
ID=49712093
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2012129429A Active JP5400924B2 (en) | 2012-06-07 | 2012-06-07 | Method for producing gold-supported carbon catalyst |
Country Status (3)
Country | Link |
---|---|
JP (1) | JP5400924B2 (en) |
TW (1) | TWI508774B (en) |
WO (1) | WO2013183704A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105457643A (en) * | 2015-12-25 | 2016-04-06 | 湖北大学 | Preparation method of active carbon loaded catalyst for electrochemically catalyzing and degrading organic wastewater |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6232505B2 (en) | 2014-10-24 | 2017-11-15 | 株式会社キャタラー | Fuel cell electrode catalyst and method for producing the same |
CN107209179B (en) | 2014-12-16 | 2019-12-20 | 积水医疗株式会社 | Test strip for immunochromatography for detecting object in sample containing red blood cells, and immunochromatography using same |
JP6635976B2 (en) | 2017-04-28 | 2020-01-29 | 株式会社キャタラー | Electrode catalyst for fuel cell and method for producing the same |
EP3767723B1 (en) | 2018-03-16 | 2024-08-21 | Cataler Corporation | Electrode catalyst for fuel cell, and fuel cell using same |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2001224968A (en) * | 2000-02-17 | 2001-08-21 | Mitsubishi Heavy Ind Ltd | Method for preparing deposited metallic catalyst and method for manufacturing solid high-polymer type fuel battery |
JP2004185994A (en) * | 2002-12-03 | 2004-07-02 | Nippon Sheet Glass Co Ltd | Fuel cell cathode, its manufacturing method and fuel cell |
JP2007250274A (en) * | 2006-03-14 | 2007-09-27 | Cataler Corp | Electrode catalyst for fuel cell with enhanced noble metal utilization efficiency, its manufacturing method, and solid polymer fuel cell equipped with this |
CN1994563A (en) * | 2006-11-21 | 2007-07-11 | 华南理工大学 | Carbon supported noble metal catalyst and method for preparing same |
JP4853498B2 (en) * | 2008-06-17 | 2012-01-11 | トヨタ自動車株式会社 | Method for producing gold fine particle supported carrier catalyst for fuel cell and catalyst for polymer electrolyte fuel cell containing gold fine particle produced by the method |
JP2010092725A (en) * | 2008-10-08 | 2010-04-22 | Hitachi Maxell Ltd | Fuel-cell catalyst and manufacturing method for the same, carbon particle carrying fuel-cell catalyst thereon, membrane-electrode assembly, and fuel cell |
US20110033353A1 (en) * | 2009-08-05 | 2011-02-10 | Basf Corporation | Preparation of Diesel Oxidation Catalyst Via Deposition of Colloidal Nanoparticles |
-
2012
- 2012-06-07 JP JP2012129429A patent/JP5400924B2/en active Active
-
2013
- 2013-06-06 TW TW102120076A patent/TWI508774B/en active
- 2013-06-06 WO PCT/JP2013/065683 patent/WO2013183704A1/en active Application Filing
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105457643A (en) * | 2015-12-25 | 2016-04-06 | 湖北大学 | Preparation method of active carbon loaded catalyst for electrochemically catalyzing and degrading organic wastewater |
CN105457643B (en) * | 2015-12-25 | 2017-12-05 | 湖北大学 | A kind of preparation method of activated carbon supported type catalyst for Electrocatalysis Degradation organic wastewater |
Also Published As
Publication number | Publication date |
---|---|
TWI508774B (en) | 2015-11-21 |
TW201412395A (en) | 2014-04-01 |
WO2013183704A1 (en) | 2013-12-12 |
JP2013252483A (en) | 2013-12-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Zuo et al. | A hollow PdCuMoNiCo high-entropy alloy as an efficient bi-functional electrocatalyst for oxygen reduction and formic acid oxidation | |
Wu et al. | Synthesis and electrocatalytic oxygen reduction properties of truncated octahedral Pt 3 Ni nanoparticles | |
EP3027308B1 (en) | Method for forming noble metal nanoparticles on a support | |
Sun et al. | Ternary PdNi-based nanocrystals supported on nitrogen-doped reduced graphene oxide as highly active electrocatalysts for the oxygen reduction reaction | |
Bharti et al. | Surfactant assisted synthesis of Pt-Pd/MWCNT and evaluation as cathode catalyst for proton exchange membrane fuel cell | |
You et al. | Improvement of activity for oxygen reduction reaction by decoration of Ir on PdCu/C catalyst | |
JP3643552B2 (en) | Catalyst for air electrode of solid polymer electrolyte fuel cell and method for producing the catalyst | |
Wei et al. | Highly efficient Pt-Co alloy hollow spheres with ultra-thin shells synthesized via Co-BO complex as intermediates for hydrogen evolution reaction | |
JP2006202761A (en) | Supported catalyst and manufacturing method for the same | |
JP5400924B2 (en) | Method for producing gold-supported carbon catalyst | |
KR20160112632A (en) | preparation method of binder-free catalytic electrodes for direct carbon fuel cell by using nickel foam and graphene aerogel and catalytic electrodes by using the same method | |
JP2016003396A (en) | Synthesis of alloy nanoparticles as stable core for core-shell electrode catalysts | |
JP4785757B2 (en) | Method for producing noble metal-supported electrode catalyst and noble metal-supported electrode catalyst obtained by the production method | |
JP6635976B2 (en) | Electrode catalyst for fuel cell and method for producing the same | |
Wang et al. | Facile synthesis of quaternary structurally ordered L12-Pt (Fe, Co, Ni) 3 nanoparticles with low content of platinum as efficient oxygen reduction reaction electrocatalysts | |
Ye et al. | A solvent approach to the size-controllable synthesis of ultrafine Pt catalysts for methanol oxidation in direct methanol fuel cells | |
Ma et al. | Structural evolution of PtCu nanoframe for efficient oxygen reduction reactions | |
JP2008041498A (en) | Method of manufacturing catalyst support body for polymer electrolyte fuel cell, and polymer electrolyte fuel cell | |
JP6956851B2 (en) | Electrode catalyst for fuel cells and fuel cells using them | |
JP2014002981A (en) | Method for producing electrode catalyst | |
KR102416422B1 (en) | Method for producing a platinum-based alloy catalyst for fuel cell | |
Martinez-Mora et al. | Platinum nanoclusters made by gas-diffusion electrocrystallization (GDEx) as electrocatalysts for methanol oxidation | |
JP2001205086A (en) | Method for manufacturing platinum/ruthenium alloy- bearing catalyst | |
WO2010138688A1 (en) | Alloy fuel cell catalysts | |
CN110988062B (en) | Preparation method of gas diffusion electrode for measuring hydrogen sulfide gas |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20130912 |
|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20130912 |
|
A871 | Explanation of circumstances concerning accelerated examination |
Free format text: JAPANESE INTERMEDIATE CODE: A871 Effective date: 20130912 |
|
TRDD | Decision of grant or rejection written | ||
A975 | Report on accelerated examination |
Free format text: JAPANESE INTERMEDIATE CODE: A971005 Effective date: 20131008 |
|
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20131017 |
|
A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20131025 |
|
R150 | Certificate of patent or registration of utility model |
Ref document number: 5400924 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |