Electrochemical corrosion of carbon materials in an aqueous acid solution

Abstract

In this fundamental study on corrosion of the carbon catalyst support in a PEMFC cathode, corrosion rates of electrodes made of carbon powder were investigated by measuring CO2 generation. The corrosion rate was affected by not only the retention potential but also by the presence of dissolved oxygen in the electrolyte. The corrosion rate showed two stages; initial corrosion was observed for several hours, and was followed by steady-state corrosion. Even in this latter stage, change to a lower potential induced a peak in the corrosion rate that exceeded the previous steady value just after the potential was restored. Corrosion was also accelerated by platinum catalyst.