HIGH UTILIZATION SUPPORTED CATALYTIC METAL-CONTAINING GAS-DIFFUSION ELECTRODE, PROCESS FOR MAKING IT, AND CELLS UTILIZING IT

摘要

Gas-diffusion electrodes (GDE's) are obtained by starting with a GDE which is fully fabricated except for electrocatalytic metal treatment and solid polymer electrolyte (s.p.e.) treatment. This untreated GDE is treated by a) impregnating an s.p.e. solution into the catalytic face until the solution penetrates part way into the cross-section of the GDE support material, but not as far as the hydrophobic, gas permeable face, b) inserting the thus-treated GDE and a counterelectrode into a plating bath containing, M<+>, M<++>, and/or M<+++> ions, where M is a metal of Group VIII or I-B of the Periodic Table, and c) applying an interrupted current to the thus-treated GDE, so metal particles < 10 nm in average particle size deposit on the particulate support material of the catalytic face, but essentially only on sites that are already in contact with the previously-deposited s.p.e.