Formate: A Possible Replacement for Formic Acid in Fuel Cells

We present a facile thermodynamic strategy for identifying formate electrooxidation at a Pt electrode in a fuel cell. Mixtures of formate and sulfuric acid are used as fuel solutions for maintaining formic acid at a low concentration and reducing CO poisoning of the Pt electrode. Pt is modified by a polyaniline porous film to improve the electrocatalytic activity towards formate oxidation. The result indicates that formate can bypass the poisoning path to form CO2 at a low potential. Additionally, we propose a new mechanism of formate electrooxidation and investigate the possibility of an independent oxidation path starting from free formate in solution.