Synthesis of Na Doped TiO2 Nano Photocatalysts Film on Its Photoactivity and Hydrophilicity

Abstract

Na/TiO2 nanocomposite films with different amounts of Na were prepared using the sol-gel process and were coated onto glass substrates by dipping methods. These composite thin films were calcined at the temperatures of 400 °C for 1 h. The effect of Na doping in TiO2 composite films on photocatalytic reaction and hydrophilic property was investigated. The phase ormation of TiO2 was characterized by XRD. The morphology of TiO2 composite films was observed using atomic force microscopy (AFM). The chemical composition of the prepared films was analyzed using FTIR spectrometry. The photoactivity of synthesized films was performed by means of degradation of methylene blue dye solution under UV and visible light irradiation. The hydrophilic property was measured in terms of contact angles of water droplets on the films at room temperature. It was found that Na doping seemed to affect the TiO2 phase, the crystallinity of the anatase phase and the crystallite size of the composite films. The crystallite size decreased with an increase in Na content which were 3, 5 and 6 mol%. It was found that 6 mol% Na/TiO2 film, having the smallest crystallite size, showed the highest photocatalytic reaction and that its films provided the most hydrophilic effect. Only the anatase phase was found at the calcination temperature of 400 °C. The high hydrophilic property was mainly related to the high level of OH radicals on its surface. The super -hydrophilicity (at the contact angle equal to zero) of all new doped TiO2 films were found at room temperature for 15 minutes.