Photoelectrocatalytic Degradation of Humic Acids Using Codoped TiO2Film Electrodes under Visible Light

Cu/N codoped TiO2films on Ti substrates were successfully prepared by electrochemical method with the goal of enhancing the photoelectrocatalytic activity under visible light. The morphology and composition of the Cu/N codoped films were characterized using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), and UV-Vis diffusion reflection spectroscopy (UV-Vis DRS). The photocatalytic activities of the Cu/N codoped TiO2films were evaluated by the degradation of humic acid. The visible light photocatalytic degradation of humic acid (HA) was tested and Cu/N codoped TiO2films showed the highest degradation efficiency up to 41.5% after 210 minutes of treatment. It showed that Cu2+and NH4+ codoped TiO2film significantly improved the photocatalytic efficiency under the visible light. When +5.0 V anodic bias potential and visible light were simultaneously applied, the degradation efficiency of HA over the Cu/N codoped TiO2films significantly improved to 93.5% after 210 minutes of treatment.