Preparation and methanol oxidation catalysis of Pt-CeO2 electrode

An electrochemical methodology to prepare platinum/cerium oxide electrodes by using glassy carbon substrates has been developed, The method involves an "occlusion deposition" of CeO2 particles at glassy carbon electrodes from a platinum bath in acid solution at an applied constant potential, The depositions were made by applying, a controlled potential of 200 mV vs. Ag/AgCl in 0.5 M H2SO4 containing K2PtCl6 and CeO2 suspensions. The deposition was done at different concentrations of K2PtCl6 and constant supersaturation concentrations of CeO2. The final composite electrodes were characterized by using X-ray fluorescence/energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The catalytic properties or the composite electrodes were tested for the electrooxidation of methanol in acid solution by chronoamperometry and were compared to Pt only deposits on glassy carbon. (c) 2005 Elsevier B.V. All rights reserved.