Effect of heat treating on structure and optical properties of composite V₂O₅-TiO₂ thin films

V₂O₅-TiO₂ composite thin films were prepared by sol-gel process with Ti (C₄H₉O)₄ and V₂O₅ powder as the starting materials. The thin films were characterized by XPS and UV-vis-nir spectrophotometer. With increase of heating temperature, content of V⁴⁺ decreases and that of V⁵⁺ increases gradually while that of Ti⁴⁺ remains as before; theoretical curves of the film agree with the experimental curves well through simulating of superposition integral; the transmittance of the films in the ultraviolet range falls remarkably and the absorption edges take a red shift with the increase of heating temperature.