Patent ID: 9634333
Date: 2017-04-25
CPC Classifications: H01M,Y02E

Claim:
1. A method for producing a catalyst paste for a fuel cell, in which a catalyst metal particle including a noble metal is supported on a carrier, the method characterized by comprising the steps of: preparing an unmodified catalyst metal particle supported on a carrier; modifying the unmodified catalyst metal particle with at least one type of modifying group selected from a nitric acid group, an amino group, a sulfonic acid group, a hydroxy group, and halogen groups to obtain a modified catalyst metal particle having a hydrophilic region formed thereon, wherein, in the step of modifying, the unmodified catalyst metal particle supported on the carrier binds a complex of the noble metal, including the modifying group, and changes to said modified catalyst particle, wherein the modifying group exists on the surface of the catalyst metal particle and is not separated from the catalyst metal particle; forming a pre-paste by mixing the modified catalyst with water; and forming a catalyst paste by mixing the pre-paste with a solution of an electrolyte to form a carrier-supported catalyst having a polymer electrolyte phase surrounding a periphery of the catalyst with the hydrophilic region interposed therebetween.