Evaluation on the Property of Methanol Oxidation by Phosphomolybdic Acid

Abstract

Direct methanol fuel cell (DMFC) has been appreciated extensively because it is abundant in source, cheap in price, safe in transportation and storage. Though catalyst poisoning easily occurs by CO generated from the reaction of methanol oxidation, simultaneously, the efficiency of fuel cell decreases and environmental pollution is caused due to the methanol permeation through proton exchange membrane, application of DMFC is restricted. Phosphomolybdic acid (POM) is attempted to be used as energy storage material in this paper. The energy is stored in reduced POM through methanol oxidation by POM over different catalysts. Electrochemical oxidation of reduced POM produces electricity on the anode of PEMFC. Experimental results showed that under the non-photocatalytic condition methanol could be oxidized by POM over Pt/SiO2 and Ru/SiO2 catalyst. Only CO2 and H2O are yielded in the reaction. The activities for two kinds of catalyst increased with the increasing of reaction temperature and methanol concentration. Apparent activation energy for Pt/SiO2 catalyst was less than that for Ru/SiO2 catalyst. Activity of Pt/SiO2 catalyst is obviously higher than that of Ru/SiO2 catalyst. POM as energy storage material is feasible.