Preparation By Hydrothermal Method, Characterization And Photocatalysis Application Of Some Inorganic Nanomaterials

Among the technologies to remove environmental pollutants, photocatalytic is recognized as one of the most promising technology. Nowadays, through simple,green route to synthesize new and high efficiency nono-photocatalyst is the hindrance for the photocatalytic technology further development. In this dissertation, a green route-hydrothermal method was developed to prepare different nanomaterials, research the factors on the mophorlogy of these nanomaterials, to achieve controlled synthesis of materials' morphology. The photodegradation of acetone and RhB were employed as a probe reaction to test the photolytic activities of these as-prepared samples. The products were characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (SEM), Raman spectroscopy and fluorescence spectroscopy. The main points are summarized as follows:1. MnW04 with different morphologies were synthesized by a simple hydrothermal method with MnCl2·4H2O and Na2WO4·2H2O as source materials. The products were characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (SEM), Raman spectroscopy and fluorescence spectroscopy. The results reveal that pH value plays an important role in the morphology and phase of samples. A simple reaction mechanism for the formation of MnWO4 were presented. The photodegradation of acetone was employed as a probe reaction to test the photocatalytic activities of the as-prepared samples.2. PbS nanodendrites were prepared by a simple hydrothermal process from Pb(NO3)2 and thiourea (NH2CSNH2) at 120℃without any additives. The structure and morphology of obtained-samples were characterized by X-ray powder diffraction (XRD) and field-emission scanning electron microscopy (SEM). The effect of Pb and S source, the ratio of Pb/S or CTAB/EDA and pH value on the morphologies of the products were investigated. A possible formation mechanism of PbS nanocrystals was discussed. The photocatalytic property of PbS dendrites was also investigated. It was found that the novel nanocrystals have high catalytic efficiency for the degradation of Rhodamine B (RhB) under visible irradiation.3. A combined chemical mechod with CCD imaging analysis system was used to choice the high activity photocatalyst. By using the technologies, we have screened several TiO2 doped metallic oxide photocatalysts and found that V2O5/TiO2 is a good one for the degradation of basic green. The doping of V2O5 into TiO2 retards the recombination of electron-hole pairs in catalysts and makes the catalysts activate in visible light. The reaction results indicated that when the mole ratio of V20s/TiO2 prepared by sol-gel method is 15%, the degradation rate of basic green reaches 96% under visible light.