Fabrication of a novel Ti/SnO2–Sb–CeO2@TiO2–SnO2 electrode and photoelectrocatalytic application in wastewater treatment

A TiO2/SnO2 composite thin film was coated onto a Ti/SnO2–Sb–CeO2 electrode through a simple sol–gel route. Under illumination, the photocurrent in the Ti/SnO2–Sb–CeO2@TiO2-SnO2 thin film reached its maximum value under a bias potential of 1.5 V. Methylene blue (MB) was used as model compound in wastewater to determine the photoelectrocatalytic (PEC) activity of the electrode. Cyclic voltammetry results indicate that 1.02 V is the oxidation degradation peak of MB. The resistance could be decreased by applying a potential bias under illumination. The key factors affecting the PEC efficiency, such as the applied bias potential and light intensity, were also assessed. The best performance of MB degradation was obtained with a potential bias of 1.5 V under a light intensity of 60.2 mW/cm2. We observed high efficiency of MB degradation (96%) with the PEC oxidation process, as compared with the efficiencies of the conventional electrochemical oxidation (63%) and photocatalysis processes (84%).