High Performance, Platinum Activated Tungsten Oxide Fuel Cell Electrodes

Abstract

HYDROCARBON fuels (methane, propane and so on) are relatively inert and can only be electrochemically oxidized using either high loading noble metal-black electrodes in phosphoric acid at 150° C or high temperature molten carbonate (or solid oxide) electrolyte cells at 600–1,000° C (ref. 1). Alternatively the fuel may be “reformed”, producing impure hydrogen (containing carbon dioxide and some carbon monoxide) which may be fed into a low temperature (> 100° C) acid fuel cell. Carbon monoxide, however, poisons platinum black by strongly adsorbing on its surface (with high coverage) at normal fuel cell anode potentials. Little opportunity exists for water molecules to adsorb on sites adjacent to surface CO molecules—a necessary condition for the removal of the latter by anodic oxidation²