Effect of Temperature on the Catalytic Property of Pd-P for the Formic Acid Oxidation Reaction

The development of active anode catalysts for the oxidation of formic acid is of great importance in direct formic acid fuel cells, which show promising prospect as a potential power generator for portable electronic devices and vehicular applications. Herein, carbon supported palladium-phosphorus (Pd-P/C) catalysts with a high content of P-0 are successfully prepared at different temperatures and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) and so on. The effects of the synthesis temperature on the activity and stability of Pd-P/C catalysts for formic acid oxidation are also investigated by electrochemical measures. The results of the study indicate that the catalytic activity of the catalysts toward formic acid oxidation decreases in the order of Pd-P-85> Pd-P-45>Pd/C > Pd-P-25 (the numbers refer to the preparation temperatures of the samples), and the stability of the four catalysts determined by the ratio between the steady-state current and initial current through chronoamperometric measurements is in the following order: Pd-P-85 > Pd-P-45 > Pd-P-25 > Pd/C. The Pd-P/C catalysts prepared at elevated temperatures are more stable and active than the Pd/C catalyst because of the inclusion of P. Therefore, the Pd-P/C catalyst prepared at appropriatetemperature is a promising anode catalyst indirect formic acid fuel cells