Method for producing fuel cell electrode catalyst

• US 9,947,940 B2
• Filed: 08/26/2014
• Issued: 04/17/2018
• Est. Priority Date: 12/27/2013
• Status: Active Grant

• Current Assignee: Showa Denko KK
• Original Assignee: Showa Denko KK
• Inventors: Zhu, Kunning, Lee, Kunchan
• Primary Examiner(s): Soliman, Haytham
• Application Number:
  US15/103,383
• Publication Number:
  US 20160359172A1
• Time in Patent Office: 1,330 Days
• Field of Search: 502325
• CPC Class Codes: H01M 4/88 Processes of manufacture
• CPC Class Codes: H01M 4/921 Alloys or mixtures with metallic elements
• CPC Class Codes: H01M 4/925 supported on carriers, e.g. powder carriers
• CPC Class Codes: H01M 4/926 on carbon or graphite
• CPC Class Codes: H01M 4/928 Unsupported catalytic particles; loose particulate catalytic materials, e.g. in fluidised state
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A method is provided for producing a platinum alloy-containing fuel cell electrode catalyst with high activity which is suited for its industrial mass-production. The method for producing a fuel cell electrode catalyst includes a step of preparing a dispersion in which particles of a fuel cell electrode catalyst precursor including a platinum alloy is dispersed in an electrolyte solution, and a step of alternately subjecting the dispersion to bubbling with an oxidizing gas and to bubbling with an inert gas or a reducing gas.

Claims

1. A method for producing a fuel cell electrode catalyst comprising:

a step of preparing a dispersion in which a fuel cell electrode catalyst precursor comprising a platinum alloy is dispersed in an electrolyte solution, and

a step of alternately subjecting the dispersion to bubbling with an oxidizing gas and to bubbling with an inert gas or a reducing gas.

2. The method for producing a fuel cell electrode catalyst described in claim 1, wherein the electrolyte solution is an aqueous sulfuric acid solution, an aqueous perchloric acid solution, hydrochloric acid or an aqueous nitric acid solution.

3. The method for producing a fuel cell electrode catalyst described in claim 1, wherein the oxidizing gas is an oxygen gas.

4. The method for producing a fuel cell electrode catalyst described in claim 1, wherein the inert gas or the reducing gas is an inert gas.

5. The method for producing a fuel cell electrode catalyst described in claim 4, wherein the inert gas is nitrogen gas.

6. The method for producing a fuel cell electrode catalyst described in claim 1, wherein the step of alternately subjecting the dispersion to bubbling with an oxidizing gas comprises subjecting the dispersion to bubbling with an oxidizing gas for at least 5 minutes so as to oxidize surfaces of the platinum alloy and to bubbling with an inert gas or a reducing gas for at least 5 minutes so as to reduce oxidized surfaces of the platinum alloy.

7. The method for producing a fuel cell electrode catalyst described in claim 1, wherein the platinum alloy contains platinum and one or more other metal elements in a molar ratio of platinum:

other metal element(s)=1;

0.1 to 10.

8. The method for producing a fuel cell electrode catalyst described in claim 1, wherein bubbling with the oxidizing gas is carried out until a difference in potential of the electrode catalyst precursor after bubbling is not less than 0.03 V.

9. The method for producing a fuel cell electrode catalyst described in claim 1, wherein bubbling with an inert gas or a reducing gas is carried out until a difference in potential of the electrode catalyst precursor after bubbling is not more than −

0.03 V.