Use of an anode catalyst layer

Patent metadata

Field	Value
Publication number	US-9947939-B2
Application number	US-201414765699-A
Country	US
Kind code	B2
Filing date	Jan 29, 2014
Priority date	Feb 5, 2013
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

A method of operating a fuel cell having an anode, a cathode and a polymer electrolyte membrane disposed between the anode and the cathode, includes feeding the anode with an impure hydrogen stream having low levels of carbon monoxide up to 5 ppm, and wherein the anode includes an anode catalyst layer including a carbon monoxide tolerant catalyst material, wherein the catalyst material includes: (i) a binary alloy of PtX, wherein X is a metal selected from the group consisting of rhodium and osmium, and wherein the atomic percentage of platinum in the alloy is from 45 to 80 atomic % and the atomic percentage of X in the alloy is from 20 to 55 atomic %; and (ii) a support material on which the PtX alloy is dispersed; wherein the total loading of platinum group metals (PGM) in the anode catalyst layer is from 0.01 to 0.2 mgPGM/cm 2 .

First claim

The invention claimed is:

1. A method of operating a fuel cell comprising an anode, a cathode and a polymer electrolyte membrane disposed between the anode and the cathode, wherein said method comprises feeding the anode with an impure hydrogen stream comprising low levels of carbon monoxide up to 5 ppm, and wherein the anode comprises an anode catalyst layer comprising a carbon monoxide tolerant catalyst material, wherein the catalyst material comprises:
(i) a binary alloy of PtX, wherein X is osmium metal, and wherein the atomic percentage of platinum in the alloy is from 45 to 75 atomic % and the atomic percentage of X in the alloy is from 25 to 55 atomic %; and
(ii) a support material on which the PtX alloy is dispersed; wherein the total loading of platinum group metals (PGM) in the anode catalyst layer is from 0.01 to 0.2 mgPGM/cm 2 .

2. The method according to claim 1 , wherein X is Os.

3. The method according to claim 2 , wherein the atomic percentage of Pt in the binary alloy is from 50 to 75 atomic % and the atomic percentage of X is from 25 to 50 atomic %.

4. The method according to claim 2 , wherein the amount of platinum in the supported catalyst is 10-50 wt % of the total weight of the binary alloy plus support material.

5. The method according to claim 2 , wherein the anode further comprises a second catalyst.

6. The method according to claim 5 , wherein the second catalyst is an oxygen evolution catalyst.

7. The method according to claim 1 , wherein the atomic percentage of Pt in the binary alloy is from 50 to 75 atomic % and the atomic percentage of X is from 25 to 50 atomic %.

8. The method according to claim 7 , wherein the amount of platinum in the supported catalyst is 10-50 wt % of the total weight of the binary alloy plus support material.

9. The method according to claim 7 , wherein the anode further comprises a second catalyst.

10. The method according to claim 9 , wherein the second catalyst is an oxygen evolution catalyst.

11. The method according to claim 1 , wherein the amount of platinum in the supported catalyst is 10-50 wt % of the total weight of the binary alloy plus support material.

12. The method according to claim 11 , wherein the anode further comprises a second catalyst.

13. The method according to claim 12 , wherein the second catalyst is an oxygen evolution catalyst.

14. The method according to claim 1 , wherein the anode further comprises a second catalyst.

15. The method according to claim 14 , wherein the second catalyst is an oxygen evolution catalyst.

Assignees

• Johnson Matthey Fuel Cells Ltd

Inventors

• O'Malley Rachel Louise
• Petrucco Enrico

Classifications

• Y02E60/50

  Fuel cells · CPC title

• B01J21/18

  Carbon · CPC title

• H01M8/1004

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title

• B01J23/6484

  Niobium · CPC title

• H01M4/8828

  Coating with slurry or ink · CPC title