A novel method to synthesize molybdenum doped TiO2 films with enhanced photocatalytic activity

Micro arc oxidation method was utilized to prepare molybdenum doped TiO2 films through adding sodium molybdate into the electrolyte for the first time. The effect of sodium molybdate concentration on the morphology, crystal structure and photophysical properties of the films was investigated by field emission scanning electron microscopy, X-ray diffraction and UV-vis spectrophotometry. The results showed that with increasing of sodium molybdate concentration, the pores of films decreased in size and increased in number, more anatase phase transformed to rutile phase in the films and interplane spacing of the films increased. Furthermore, the absorption edges of the films shifted towards longer wavelength and the band gap energies of the films decreased with increasing the concentration of sodium molybdate. In addition, the photocatalytic degradation of methylene blue showed that the photocatalytic activity of the molybdenum doped TiO2 film was about 2.3 times that of pure TiO2 film.