New solid polymer electrolyte composites for water electrolysis

A new procedure for the preparation of SPE-electrocatalyst composites has been developed. In this procedure, noble metal cationic species are chemically reduced within a solid polymer electrolyte. The metallic particles are not homogeneously distributed across the SPE thickness but predominate near its surfaces. The structure and the distribution of the precipitates, along the membrane thickness have been investigated by scanning electron microprobe analysis and transmission electron microscopy. Application to SPE water electrolysis has been performed using Nafion membranes and platinum-group electrocatalysts. The SPE-electrocatalyst composites prepared according to this new procedure present good electrochemical properties, low catalyst loadings, long-time stability and high energetic efficiencies.