Effect of Electrolyte on Electrocatalytic Performance of Carbon Supported Pd Catalyst for Formic Acid Oxidation

In order to understand the effect of (NH(4))(2)SO(4), K(2)SO(4) and H(2)SO(4) electrolytes on the electrocatalytic performance and the mechanisim of the Pd/C catalyst electrode for formic acid oxidation, the performance of the said electrode for formic acid oxidation in different electrolytes were evaluated using electrochemical methods. The results show that the electrocatalytic activity and stability are decreased according to the following order: (NH(4))(2)SO(4)>. K(2)SO(4)>H(2)SO(4). Because of the existence of formic acid, the difference in the pH value of different electrolytes is small. Thus, the effect of the pH value of the electrolytes is small. Moreover, the conductivity of the electrolytes would affect the peak potential of the formic acid oxidation. Finally, NH(4)(+) plays a special rule. It could decrease the amount of CO adsorbed on the Pd/C catalyst. The electrocatalytic performance of the Pd/C catalyst for formic acid oxidation in (NH(4))(2)SO(4) electrolyte is the best among three electrolytes.