Electrochemical catalytic activity for the hydrogen oxidation of mesoporous WO3 and WO3/C composites

Abstract

New catalysts for hydrogen oxidation, mesoporous WO3 and WO3/C composites, have been synthesized by a simple one-step casting method using mesoporous silica (KIT-6) as hard template. The materials were characterized with XRD, XPS, TEM and N2 sorption techniques. Cyclic voltammetry (CV) and single cell test for hydrogen oxidation were adopted to characterize the electrochemical performance of the materials. The mesoporous WO3 has a high surface area of 86 m2 g−1 and a well-crystallized framework. This material exhibits stable electrochemical activity for hydrogen desorption/oxidation in half-cell experiments, and after mixing with the appropriate amount of carbon black the resultant mesostructured WO3/C composites show further enhanced electrocatalytic activity and even higher hydrogen oxidation/reduction peak currents than the commercial catalyst 20 wt% Pt/C. The single cell test results indicate that the mesostructured WO3/C composites have clear current output in a proton exchange membrane fuel cell (PEMFC) and exhibit electrochemical catalytic activity toward hydrogen oxidation, and appears to be a potential anode catalyst in PEMFCs.