Study On The Preparation And Properties Of TiO₂ And ZnO Photocatalytic Materials Sensitized By CdSe

In recent years, with the development of pollution control technology in printing and dyeing industry, photocatalytic oxidation technology was applied in the field of environmental pollution control. Nano-scaled TiO₂ and ZnO materials are expected to play an important role for the degradation of environmental pollution due to its good characteristics of powerful oxidation strength, high chemical stability, and nontoxicity. The preparation of nano-TiO₂ and ZnO has been studied deeply for many years, however seldom reports can be found about the preparation of nano-TiO₂ and ZnO in anhydrous liquid phase system.The preparation and of nano-Ti O₂ and ZnO in the anhydrous liquid system and photocatalytic application were mainly studied in this paper. Nano TiO₂ and ZnO materials were prepared with Tetrabutyl titanate and zinc acetate two water as precursor respectively, and the nano-TiO₂ and ZnO samples was characterized by differential scanning infrared spectroscopy（IR）, X-ray diffraction（XRD）, Scanning electron microscope（SEM）. The CdSe semiconductor was composite modified on this basis.The effects of the reaction temperature, the concentration of the main reactant and the mole ratio of the reactants on the preparation of the photo catalyst were investigated in the process of preparation of nano TiO₂ and ZnO. The results showed that the anatase type nano TiO₂ can be successfully prepared with the temperature of 140℃, tetrabutyl titanate volume fraction 30%, titanium and acetic acid ratio of 1:2. The hexagonal wurtzite structure anatase nano-ZnO was prepared with the reaction temperature of 140℃, zinc acetate two water volume fraction 10%, zinc acetate two water and ethanediamine ratio of 25:18.The experiment of photocatalytic degradation under the UV irradiation was carry out for evaluation of catalyst performance by aryl methanes（basic fuchsin） and azo（methylene blue） dyes as simulated degradation objects. The results show that Nano-TiO₂ and ZnO were prepared by alcohol-thermal to basic fuchsine and Methylene Blue has photocatalytic performance. The Photocatalytic effect of Nano-TiO₂ was better than ZnO. Nano-Ti O₂ and ZnO improve the efficiency of photocatalytic degradation of basic fuchsine and Methylene Blue by CdSe composite modification. When the irradiation time is 20 min, TiO₂ and CdSe-TiO₂ respectively for the degradation of basic fuchsine rate is 38.38% and 93.19%, for the degradation of Methylene Blue rate is 37.15% and 68.84%, CdSe compound modification of basic fuchsine and methylene blue catalytic efficiency were increased by 54.81% and 31.68%; ZnO and CdSe-ZnO respectively for the degradation of basic fuchsine rate is 33.86% and 74.13%, for the degradation of Methylene Blue rate is 25.29% and 59.27%, CdSe compound modification of basic fuchsine and Methylene blue catalytic efficiency were increased by 40.27% and 33.98%.