Self-Cleaning TiO<sub>2</sub> Nanofilms on FTO Glass: Influence of Electrophoretic Deposition and UV Irradiation Conditions

Abstract

In this research, anatase TiO2nanoparticles were electrophoretically deposited on the FTO glass. This investigation was focused on the self-cleaning property of TiO2coatings and the effects of different parameters on this characteristic such as: applied voltages during electrophoretic depositions and durations of UV irradiation. Electrophoretic depositions of suspensions were performed in different voltages of 10, 30 and 60 V (for 10 s) at room temperature. TiO2coatings were sintered in 450°C for 1 hr. The phase transformation of TiO2films was considered using XRD. Morphology, average particle size and the thickness of TiO2films was analyzed using FESEM microscope. The photocatalytic activity of TiO2films was evaluated by the degradation of aqueous methyl orange (MO) under UV irradiation. The ultraviolet-visible spectrophotometer was used to record the changes of the adsorbancy of the MO solution. Hydrophilicity of TiO2films was determined by measuring contact angle of water droplet with the surface of TiO2films. Results represented that decomposition rate of MO solution by TiO2films enhances from 6.5% to 31% by increasing applied voltage of deposition from 10 to 60V and from 5% to 40% by increasing UV illumination duration from 1 to 5 hours. It was also observed that the contact angles of water droplet with the surface of TiO2films decrease from 34oto 6.6oby increasing applied voltage from 10 to 60V.