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With the rapid development of modern industry, waste water, waste gas emissions to a large number of human survival environment become more and more serious damage. Semiconductor photocatalysis can be air or water, hydrocarbons, dyes, pesticides oxidation of organic pollutants such as H2O, CO2 and other small molecules, and this technology also has high activity, non-toxic and safe, relatively inexpensive, etc., so the semiconductor photocatalytic technology in environmental pollution control has become a research hotspot. Nano-TiO2 is commonly used semiconductor photocatalyst, but there are some flaws itself, for example: a wide band gap, photo-generated electron - hole easy to produce invalid composite, low utilization of sunlight and so on. Study found that the use of two or more semiconductor composite photocatalyst, can effectively improve the photocatalytic activity, and can be used in the spectral range from the ultraviolet to the visible region to expand, thereby improving the utilization of sunlight. In this thesis, the source of tin tin dichloride, cetyl trimethyl ammonium bromide (CTAB) as a soft template by sol - gel method nanometer SnO2, and on this basis, prepare Sn02/TiO2, CuO/SnO2/TiO2 nanocomposites. Discusses the process of product formation and photocatalytic reaction mechanism, the effects of different factors on the photocatalytic activity of the product. The main contents are as follows: 1 nanometer SnO2 Preparation and Photocatalytic Properties of CTAB as a soft template by using the sol - gel method nanometer SnO2. Respectively, using the SEM, XRD, IR, UV-Vis, PL and other analytical testing methods were used to characterize the resulting product, the results showed that nano-Sn02 with rutile structure, and its size is about 17 nm. Sunlight degrades methylene blue and alizarin red experimental results show that the nano-Sn02 having a photocatalytic activity. The formation mechanism of nano-Sn02 and photocatalytic reaction mechanism was discussed. 2, SnO2/TiO2 Nanocomposites Preparation and Photocatalytic Properties with CTAB as a soft template, SnCl2, and Ti (OC4H9) 4 as raw materials by sol - gel method SnO2/TiO2 nanocomposites were characterized by XRD, SEM, UV-Vis, IR and other analytical testing methods were used to characterize the resulting product, the results show that the compound has the structure of anatase and rutile structure, and its size is about 15nm. Daylight methylene blue and alizarin red to simulate pollutant studied the nano-composite photocatalytic activity, the results showed that, SnO2 incorporation improve the photocatalytic activity of TiO2. Discussed SnO2/TiO2 nanocomposite formation mechanism and photocatalytic reaction mechanism. 3, CuO/SnO2/TiO2 Nano Composites and Photocatalytic Property to CTAB as a template, using the sol-gel prepared CuO/SnO2/TiO2 three yuan nanocomposites using SEM, XRD, UV-Vis, IR and other analytical testing products were characterized by means of the results showed that the compound has a monoclinic structure, and its size is about 11nm. Studied CuO/SnO2/TiO2 complexes of methyl orange photocatalytic effect discussed doping ratio, pH, H2O2 photocatalytic degradation effect.
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