Platinum is the most efficient electrocatalyst for accelerating the oxygen reduction reaction in fuel cells. Under operating conditions, though, platinum catalysts can dissolve. When used in place of pure platinum, platinum-metal oxide composites can spare the precious metal when used as fuel cell catalysts.
Metal oxides are not typically conductive enough to be good substrates for electrochemical deposition of metals. In the inventive method, non-noble metal cations are first adsorbed onto the surface of a metal oxide core. The cation adsorbate is then reduced to provide an appropriate surface for the subsequent deposition of noble metal from a solution of metal salts.
Applications and Industries
Fuel cell catalysts; oxygen reduction; heterogeneous catalysis.
Electrocatalysts made from layers of noble metals, such as platinum, on metal oxide cores stabilize the noble metal against dissolution, resulting in a longer catalytic lifetime compared to bulk platinum/carbon catalysts.