Method of preparing a cathode electrocatalyst

Abstract

Disclosed is an electrode having a substrate with an elecrically active surface film. The film has a relatively imporous, dense portion in contact with the substrate and containing cobalt, tungsten, and phosphorous, and a less dense, more porous portion containing oxycompounds of cobalt. Also disclosed is a method of preparing the electrode by electroless deposition of cobalt, tungsten, and phosphorous onto a metallic substrate and heating of the substrate in the presence of oxygen to a temperature and for a time sufficient to form filament-like cobalt oxycompound elements extending outwardly from the surface of the film.

Dependencies are inferred from the claim text.