Performance and durability of PtCo alloy catalysts for oxygen electroreduction in acidic environments

Abstract The performance and durability of PtCo alloy catalysts for oxygen electroreduction in acidic environments were investigated by the electrochemical rotating disk electrode (RDE) technique, in situ electrochemical scanning tunneling microscopy (STM), and inductively coupled plasma-optical emission spectroscopy (ICP-OES). In comparison with benchmark Pt catalysts, PtCo alloy catalysts offer both enhanced catalytic activity towards molecular oxygen electroreduction and improved durability under electrochemical forces in acidic environments for short-term operation; however, PtCo alloy catalysts do not provide long-term improvement in catalytic activity and electrochemical durability due to the leaching of elemental cobalt from the alloys under intensive potential cycling. Therefore, similar to Pt, PtCo alloys are not viable cathode catalysts for low temperature fuel cells for transportation applications.