Comparison of the Photocatalytic activity of TiO2 with the TiO2:SiO2 thin film

Abstract

Nanocrystalline films of TiO2 and TiO2:SiO2 with high photocatalytic activity was prepared on glass substrate via the sol-gel method. The films were subjected to high temperature treatment at 500˚C for growing TiO2 crystals. Energy Dispersive X-ray Spectroscopy (EDS) was used to indicate the elements in the films. The EDS result showed that besides Ti, O and Si elements, there were small amounts of Ca, Na and Mg presented in the film that were diffused from the glass substrate. X-ray diffraction (XRD) analysis indicated that TiO2:SiO2 films contain only anatase phase. Scanning electron microscopy (SEM) was used to study the films surface morphology. The TiO2:SiO2 films that were contacted with methyl orange (MO) in the aqueous solution (10 mg.L-1) and irradiated with UV showed a high photocatalytic activity. UV spectrophotometry technique was used to monitor the degradation of methyl orange (MO) by the reduction of main absorbance peak at 464 nm. The results showed that complete degradation was achieved after 1.5 hr.