ANODIC-OXIDATION OF METHANOL ON PT WO3 IN ACIDIC MEDIA/

The details of the preparation and characterization of co-deposited Pt /WO3 electrodes are presented. X-ray, scanning, and transmission elect ron microscopic studies revealed that WO3 is amorphous and that approx imately 40 angstrom Pt crystallites are uniformly dispersed in the dep osit. The influence of the deposition conditions and the effect of the solution acidity on the activity of such electrodes for methanol oxid ation have been studied. The results demonstrated that the Pt/WO3 elec trodes are much more active and more resistant to poisoning than Pt or Pt/Ru alloy catalysts. The reaction mechanism was studied by various electrochemical and surface analysis techniques. A reaction scheme tha t involves successive stepwise dehydrogenation of methanol, formation/ oxidation of hydrogen tungsten bronze, and oxidation of organic interm ediates and CO at the Pt/WO3 interface is proposed.