Electrode catalyst, composition for forming gas diffusion electrode, gas diffusion electrode, film / electrode assembly, and fuel cell stack

摘要

An electrode catalyst having excellent catalytic activity which contributes to the cost reduction of PEFC.The electrode catalyst includes a hollow carbon carrier having a pore size of 2 to 50 nm and a catalyst particle supported on the carrier.The catalyst particles are supported on both the inside and outside of the mesopores of the support and have a shell portion formed on the carrier and a shell portion covering at least a portion of the surface of the core portion.The particle size distribution of the catalyst particles was analyzed by the electron microscope tomography. The proportion of the catalyst particles supported in the mesopores is 50% or more.