Photoelectrochemical Oxidation of Benzylic Alcohol Derivatives on BiVO4/WO3 under Visible Light Irradiation

The photo-assisted electrochemical oxidation of benzylic alcohol derivatives was achieved with excellent yields up to 97% at low applied potential under visible light irradiation (> 420 nm) by using a BiVO4/WO3 photoelectrode in aprotic organic media. The faradaic efficiencies for the oxidation of 1-phenylethyl alcohol was very high (> 99%) in 0.1 M Bu4NBF4/MeCN. The applied potentials for the oxidation of benzylic alcohols (approximately + 0.7 V vs. SHE) were considerably lower than those of the Pt electrodes (approximately + 1.9 V vs. SHE). The turnover number of moles of oxidation product per moles of BiVO4 was approximately 1200.