Photoelectrocatalytic Degradation of Humic Acids Using Codoped TiO2 Film Electrodes under Visible Light

Cu/N codoped TiO2 films 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 TiO2 films were evaluated by the degradation of humic acid. The visible light photocatalytic degradation of humic acid (HA) was tested and Cu/N codoped TiO2 films showed the highest degradation efficiency up to 41.5% after 210 minutes of treatment. It showed that Cu2+ and NH4+ codoped TiO2 film 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 TiO2 films significantly improved to 93.5% after 210 minutes of treatment