Electrode for fuel cell, membrane-electrode assembly for fuel cell comprising the same, fuel cell system comprising the same, and method for preparing the electrode

• US 20050287418A1
• Filed: 05/11/2005
• Published: 12/29/2005
• Est. Priority Date: 06/23/2004
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: Kim, Hee-Tak, Lee, Jong-Ki, Kweon, Ho-Jin, Noh, Hyung-Gon
• Granted Patent: US 9,346,673 B2
• Time in Patent Office: Days
• US Class Current: 429/483
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01M 2008/1095 Fuel cells with polymeric electrolytes
• CPC Class Codes: H01M 4/8605 Porous electrodes
• CPC Class Codes: H01M 4/8807 Gas diffusion layers
• CPC Class Codes: H01M 4/8817 Treatment of supports before application of the catalytic active composition coated porous composites H01M8/0245
• CPC Class Codes: H01M 4/8867 Vapour deposition
• CPC Class Codes: H01M 4/926 on carbon or graphite
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

The electrode for a fuel cell of the invention includes: an electrode substrate; and a catalyst layer having a filler layer formed on the surface of the electrode substrate and a catalyst coating the filler layer.

Claims

1. An electrode for a fuel cell, comprising:

an electrode substrate; and

a catalyst layer comprising a filler layer formed on the surface of the electrode substrate and a catalyst coated on the filler layer.

2. The electrode according to claim 1, wherein the filler layer comprises nanocarbon.

3. The electrode according to claim 2, wherein the filler layer has a thickness from 0.05 μ

m to 10 μ

m.

4. The electrode according to claim 2, wherein the nanocarbon is selected from the group consisting of carbon nanotubes, carbon nanofibers, carbon nanowires, carbon nanohorns, carbon nanorings, and combinations thereof.

5. The electrode according to claim 2, wherein the nanocarbon has a diameter from 1 to 500 nm.

6. The electrode according to claim 2, wherein the nanocarbon has a length from 50 to 5,000 nm.

7. The electrode according to claim 2, wherein the catalyst layer comprises a filler layer comprising nanocarbon and a catalyst doposited on the filler layer.

8. The electrode according to claim 2, wherein the catalyst is provided in an amount from 0.001 to 0.5 mg/cm² per unit area.

9. The electrode according to claim 2, wherein the catalyst layer comprises a catalyst selected from the group consisting of platinum;

ruthenium;

osmium;

platinum-ruthenium alloys;

platinum-osmium alloys;

platinum-palladium alloys;

platinum-M alloys where M is a transition metal selected from the group consisting of Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and combinations thereof; and

combinations thereof.

10. An electrode for a fuel cell comprising an electrode substrate and a catalyst layer, the catalyst layer comprising:

filler particles formed on the surface of the electrode substrate;

a polymer network on the surface of the filler particles, the polymer network defining a plurality of spaces; and

catalyst particles in at least some of spaces of the polymer network.

11. The electrode according to claim 10, wherein the catalyst particles comprise a catalyst selected from the group consisting of platinum;

ruthenium;

osmium;

platinum-ruthenium alloys;

platinum-osmium alloys;

platinum-palladium alloys;

platinum-M alloys where M is a transition metal selected from the group consisting of Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and combinations thereof; and

combinations thereof.

12. The electrode according to claim 10, wherein the catalyst particles have an average diameter from 1 to 1,000 nm.

13. The electrode according to claim 10, wherein the catalyst layer comprises catalyst particles in an amount from 0.0001 to 0.4 mg/cm² per unit surface area.

14. The electrode according to claim 10, wherein the filler particles comprise particles selected from carbon particles, inorganic particles, and combinations thereof.

15. The electrode according to claim 14, wherein the filler particles comprise carbon particles selected from the group consisting of graphite, nanocarbon, and combinations thereof.

16. The electrode according to claim 14, wherein the filler particles comprise inorganic particles selected from the group consisting of alumina, silica, and combinations thereof.

17. The electrode according to claim 10, wherein the polymer network comprises a binder resin selected from the group consisting of fluorine-based binder resins, benzimidazole-based binder resins, ketone-based binder resins, ester-based binder resins, amide-based binder resins, and imide-based binder resins.

18. The electrode according to claim 17, wherein the polymer network comprises a material selected from the group consisting of poly(perfluorosulfonic acid), poly(perfluorocarboxylic acid), co-polymers of tetrafluoroethylene and fluorovinylether containing sulfonic acid groups, defluorinated polyetherketone sulfides, arylketones, poly(2,2′

-(m-phenylene)-5,5′

-bibenzimidazole), poly(2,5-benzimidazole), and combinations thereof.

19. A membrane-electrode assembly, comprising:

a polymer electrolyte membrane; and

a pair of electrodes, one positioned on each side of the polymer electrolyte membrane, each electrode comprising an electrode substrate and a catalyst layer, the catalyst layer comprising a filler layer adjacent the electrode substrate and a catalyst coating the filler layer.

20. A fuel cell system, comprising:

a fuel supply unit;

an oxidant supply unit; and

an electricity generating unit receiving fuel from the fuel supply unit and oxidant from the oxidant supply unit to generate electricity, the electricity generating unit including at least one membrane-electrode assembly and a separator, the membrane-electrode assembly comprising a polymer electrolyte membrane, and a pair of electrodes positioned on the sides of the polymer electrolyte membrane, wherein at least one of the electrodes comprises an electrode substrate and a catalyst layer comprising a filler layer adjacent the electrode substrate and a catalyst coating the filler layer.

21. A method for fabricating an electrode for a fuel cell, comprising:

forming a filler layer by wet coating the surface of an electrode substrate with nanocarbon; and

forming a catalyst layer by coating the filler layer with a catalyst.

22. The method according to claim 21, wherein the filler layer has a thickness from 0.05 μ

m to 10 μ

m.

23. The method according to claim 21, wherein the nanocarbon is selected from the group consisting of carbon nanotubes, carbon nanofibers, carbon nanowires, carbon nanohorns, carbon nanorings, and combinations thereof.

24. The method according to claim 21, wherein the catalyst is provided in an amount from 0.001 to 0.5 mg/cm² per unit surface area.

25. The method according to claim 21, wherein the catalyst layer is formed by using a deposition method selected from the group consisting of sputtering methods, Physical Vapor Deposition (PVD) methods, Thermal Chemical Vapor Deposition (CVD) methods, Plasma Enhanced CVD (PECVD) methods, thermal evaporation methods, electrochemical deposition methods, and electron beam evaporation methods.

26. The method according to claim 21, wherein the catalyst is selected from the group consisting of platinum;

ruthenium;

osmium;

platinum-ruthenium alloys;

platinum-osmium alloys;

platinum-palladium alloys, platinum-M alloy where M is a transition metal selected from the group consisting of Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and combinations thereof; and

combinations thereof.

27. A method for fabricating an electrode for a fuel cell, comprising:

forming a polymer network defining a plurality of spaces on an electrode substrate by mixing a plurality of filler particles with a binder resin to form a mixture, coating one side of the electrode substrate with the mixture to form a coated electrode substrate, drying the coated electrode substrate, and thermally treating the coated electrode substrate; and

filling at least some of the spaces of the polymer network with catalyst particles to form a catalyst layer on the electrode substrate.

28. The method according to claim 27, wherein the polymer network comprises a binder resin selected from the group consisting of fluorine-based binder resins, benzimidazole-based binder resins, ketone-based binder resins, ester-based binder resins, amide-based binder resins, imide-based binder resins, and combinations thereof.

29. The method according to claim 28, wherein the polymer network comprises a material selected from the group consisting of poly(perfluorosulfonic acid), poly(perfluorocarboxylic acid), co-polymers of tetrafluoroethylene and fluorovinylether containing sulfonic acid groups, defluorinated polyetherketone sulfides, arylketones, poly(2,2′

-(m-phenylene)-5,5′

-bibenzimidazole), poly(2,5-benzimidazole), and combinations thereof.

30. The electrode according to claim 27, wherein the filler particles comprise a material selected from the group consisting of carbon particles, inorganic particles, and combinations thereof.

31. The electrode according to claim 30, wherein the filler particles comprise carbon particles selected from the group consisting of graphite, nanocarbon, and combinations thereof.

32. The electrode according to claim 30, wherein the filler particles comprise inorganic particles selected from the group consisting of alumina, silica, and combinations thereof.

33. The method according to claim 27, wherein the catalyst is selected from the group consisting of platinum;

ruthenium;

osmium;

platinum-ruthenium alloys;

platinum-osmium alloys;

platinum-palladium alloys;

platinum-M alloys where M is a transition metal selected from the group consisting of Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and combinations thereof; and

combinations thereof.

34. The method according to claim 27, wherein the catalyst particles are an provided in an amount from 0.0001 to 0.4 mg/cm² per unit surface area.

35. The method according to claim 27, wherein the catalyst particles have an average diameter from 1 to 1,000 nm.