Studies On Preparation, Characterization, Photocatalytic Evaluation And Deactivation Behavior Of Sheet-like Nano Titania

The photocatalyst of TiO2 has greatly developed in the cleaning of environmental pollution because of its various advantages. The technique of photocatalysis has become an ideal and efficient method to remove pollutants in water and air. However, the large-scaled application of photocatalysis is limited by low efficiency, visible light no absorbing, and deactivation. In this paper, the pure and metal ion (such as Cu andâ…¤)doped TiO2 were prepared. The deactivation behavior of pure TiO2 under UV light illumination have been studied:1) Sheet-like anatase TiO2 nanoparticles were prepared by using hydrothermal method. The size of nanoparticles and their crystallinity increase with the increase of hydrothermal temperature. With the increase of nanoparticle size, the adsorption capacities and photocatalytic abilities for crystal violet become better and better. It is confinned that the nano TiO2 with small particle and high surface area is easy to be deactivated due to the covering of reactive intermediate species on surface. The sample with big particles is more stable and not easy to be deactivated, although its initial photocatalytic activity is lower than that of with the samples with small particles.2) The metal ions (such as Cu and V)doped TiO2 were also prepared by hydrothermal method. Doping in TiO2 leads to the crystalline change to some extent. The absorption threshold wavelength shows a obvious red-shift as the concentration of metal ions increase. There is an optimal metal ion concentration for the doped TiO2 to present a best photocatalytic activity.