Research On The Preparation And Properties Of WO₃-based Semiconductor Nanomaterials

The nano-modification of ordinary materials is a very effective method in endowing material with new function. Many semiconductor materials own many novel physical and chemical properties owing to their unique morphology and composition. Tungsten oxide is an n-type semiconductor, and it has many notable characteristics in physical and chemical properties. Since the1970s, Deb found that nanometer tungsten oxide has photocatalytic performances, a large number of studies had been carried out on the synthesis, photocatalytic properties, capacitive performance, photosensitive and gas-sensing properties about the nanometer tungsten oxide. In this dissertation, a series of high-quality the tungsten oxide-bsed semiconducting nanomaterials were synthesized in a ternary ethanol-ethylene golycol-water solvent system using a solvothermal route by a solvothermal synthetic method. In additional, the absorption properties of the samples were tested as potential absorbents. The photocatalytic performance of the sample was investigated by the decomposition of Rhodamine B (RhB) under visible light irradiation. The details are summarized as follows:In this paper, ethanol, ethylene glycol and water were used as solvent, and tungsten hexachloride as the source of tungsten. Nanometer tungsten oxides were obtained when the reaction conditions such as time, temperature, and the amount of the water were changed. The obtained nanometer tungsten oxides were characterized by XRD and SEM. Then, the obtained nanometer tungsten oxides were re-oxided by H2O2and the final products were characterized. The adsorption and light catalytic properties of the final products were studied. Finally, the conclusions can be obtained as following, nanometer tungsten oxides without re-oxided only has adsorption property, in which sheet nanometer tungsten oxides show good adsorption property because of its specific surface area. When the nanometer tungsten oxides were re-oxided, new heterostructure can be obtained. Nanometer tungsten oxides with heterostructure show enhanced catalytic efficiency. However,nano heterostructure will be disappeared with the increase of the oxidation time. Meanwhile, the catalytic efficiency will be reduced. So, the optimal oxidation time was obtained.