METHOD FOR MANUFACTURING CATALYST INK, METHOD FOR MANUFACTURING SOLID POLYMER FUEL CELL, AND PLATINUM-CARRYING CARBON PARTICLE

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a catalyst ink which enables the suppression of the reduction in dispersibility in catalyst ink formation, and the enhancement of durability of a solid polymer fuel cell.SOLUTION: A platinum-carrying carbon particle comprises: a carbon particle; and platinum particles carried by the carbon particle. A method for manufacturing a catalyst ink for forming an electrode catalyst layer of a solid polymer fuel cell comprises the steps of: kneading the platinum-carrying carbon particles together with water; and then, dispersing the platinum-carrying carbon particles kneaded with the water and a polymer electrolyte in a solvent other than water. An electrode catalyst layer is formed by coating a base material with the catalyst ink. In the platinum-carrying carbon particles, the platinum particles have an average particle diameter within a range of 3.0-10.0 nm. The carbon particles have a specific surface area within a range of 40-150 m/g. The amount of surface functional groups is 0.7 mmol/g or less. The platinum-carrying density is within a range of 10-50 mass%.