| 摘要 |
Disclosed is a catalyst layer constituting at least one of two gas diffusion electrodes in a membrane-electrode assembly for solid polymer fuel cells, which assembly is composed of a polymer electrolyte membrane and two gas diffusion electrodes which are bonded to the polymer electrolyte membrane while having the membrane interposed between the electrodes. In this catalyst layer, an ion conducting binder is mainly composed of a block copolymer having a particle diameter of not more than 1 μm, which copolymer has a polymer block (A) having an ion conducting group and a polymer block (B) not having an ion conducting group, which blocks are phase-separated from each other. The polymer block (A) forms a continuous phase, and a contact portion between the block copolymer and a catalyst particle is composed of the polymer block (A) having an ion conducting group. Also disclosed are a membrane-electrode assembly and a solid polymer fuel cell. |
