Characterization and photocatalytic activity of different molar ratios of TiO2 thin films prepared by Sol-Gel process

Photocatalytic application has been of large interest due to its new technology for organic pollution. Among the photocatalyst, titanium dioxide thin film is known as a photocatalyst for the elimination of organic pollutants. In this research, the structural and optical properties of TiO2 thin films prepared on glass substrates were studied, using a sol-gel (spin coating) technique. TiO2 thin films were deposited with molar ratio y between [TTIP] and [AcAc] concentration, which varied from 0.5 to 2. Photocatalytic properties of TiO2 thin films are studied by using sunlight and photodegradation of methylene blue as a water pollutant evaluated until the photocatalytic process enhances with the molar ratio. Absorbance spectra were measured using a spectrophotometer. Test results showed that the photocatalytic sunlight /TiO2 thin film is a promising method for treating wastewater. The quantity of acetylacetone in the precursor solution had no significant effect on the optical and structural properties of the TiO2 thin films. Films consisted of the anatase phase, with a band gap in the range of 3.38–3.51 eV and thickness in the range of 534–618 nm. However, the molar ratio effect on photocatalytic preperties, the best photodegradation rate reaches to 94% in y = 0.66 at t = 180 min.