Transparent nanostructured Fe-doped TiO2 thin films prepared by ultrasonic assisted spray pyrolysis technique

Nanostructured TiO 2 and Fe-doped TiO 2 thin films with high transparency were deposited on glass substrate through ultrasonic-assisted spray pyrolysis technique and were used in the visible light photocatalytic degradation of MB dye. The resulting thin films were characterized by scanning electron microscopy (SEM), Raman spectroscopy, photoluminescence spectroscopy, x-ray diffraction (XRD), and UV-visible absorption spectroscopy techniques. Based on Raman spectroscopy results, both of the TiO 2 and Fe-doped TiO 2 films have anatase crystal structure, however, because of the insertion of Fe in the structure of TiO 2 some point defects and oxygen vacancies are formed in the Fe-doped TiO 2 thin film. Presence of Fe in the structure of TiO 2 decreases the band gap energy of TiO 2 and also reduces the electron–hole recombination rate. Decreasing of the electron–hole recombination rate and band gap energy result in the enhancement of the visible light photocatalytic activity of the Fe-doped TiO 2 thin film.