Liquid phase deposition of WO3/TiO2 heterojunction films with high photoelectrocatalytic activity under visible light irradiation

• Liquid phase deposition is developed for preparing WO3/TiO2 heterojunction films.
• TiO2 film provides an excellent platform for WO3 deposition.
• WO3 expands the absorption band edge of TiO2 film to visible light region.
• WO3/TiO2 heterojunction film shows high photoelectrocatalytic activity.

ABSTRACTThe heterojunction films of WO3/TiO2 were prepared by liquid phase deposition (LPD) method via two-step processes. The scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopic analysis indicated that flower-like WO3 film was successfully deposited on TiO2 film with the LPD processes. The TiO2 film provided an excellent platform for WO3 deposition while WO3 obviously expanded the absorption of TiO2 film to visible light. As the result, the heterojunction film of WO3/TiO2 exhibited higher photocurrent response to visible light illumination than pure TiO2 or WO3 film. The photoelectrocatalytic (PEC) activity of WO3/TiO2 film was evaluated by degrading Rhodamin B (RhB) and 4-chlorophenol (4-CP) under visible light irradiation. The results showed that the LPD WO3/TiO2 film possessed high PEC activity for efficient removal of various refractory organic pollutants.