Photocatalytic Oxidation of Ethanol During Hydrogen Generation from Water-Ethanol Mixture over Gadolinium-Doped Titania

Photocatalytic hydrogen generation from wa ter in the presence of ethanol as a sacrificial reagent was studied over gadolinium doped TiO2 photocatalyst. Photocatalytic path ways of ethanol oxidation were studied with liquid 1H NMR spectroscopy. The 1H NMR results were compared with amounts of evolved hydrogen and carbon dioxide. Acetal dehyde, acetic acid, glycolic acid and glyoxylic acid were found as major intermediates of this process, whereas carbon dioxide evolution was the last step during ethanol photooxidation process. The mechanism of ethanol photooxidation has been proposed.