Electro-oxidation of ethanol and acetaldehyde on platinum single-crystal electrodes.

The electrochemical oxidation of ethanol and acetaldehyde in sulfuric acid and perchloric acid were studied at Pt (111), Pt (110), and a number of Pt [n(l11)x(111)] single-crystal electrodes. The oxidation of ethanol shows a marked dependence on the surface structure, roughly increasing as the surface step density increases. The oxidation of acetaldehyde shows a reversed correlation, the activity decreasing with increasing step density. Based on the results obtained here and reported earlier in electrochemical and ultrahigh vacuum literature, a detailed reaction scheme for the ethanol oxidation mechanism is suggested.