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Nanometer semiconductor photocatalytic material able to completely oxidize organic and inorganic pollutants in water and air purification, the destruction of bacteria and viruses, the use of solar water decomposition has been studied extensively. ZnO, TiO2 photocatalytic materials is the most representative, with high photocatalytic activity, chemical stability, thermal stability, photocatalytic degradation, extensive research and background in the field of pollution control. While taking advantage of the differences in the nature of the complementarity of the two semiconductor can increase the activity of the catalyst, therefore, ZnO-TiO2 is also very promising hot material. Wurtzite ZnO nanocrystalline zinc acetate dihydrate and sulfuric acid titanyl starting material with sodium hydroxide to adjust the pH value, the use of the NAC-FAS process direct synthesis of a spherical morphology approximation, the average particle diameter of 15nm and 5nm anatase TiO2 Nanocrystals NAC-FAS stars to step synthesis process Synthesis of approximately spherical morphology, average particle diameter of 12nm-15nm of the ZnO-TiO2 Nanocrystals. Alcohol to water ratio, pH, reaction time, microwave treatment process parameters such as the synthesis of nanocrystalline grain size, crystal structure and morphology of discussion NAC-FAS process synthesis of nanocrystalline chemical synthesis mechanism . Discuss the microwave treatment, heat treatment, and different Zn / Ti ratio of the pH value of the synthesis of nanocrystalline ZnO, TiO2 and ZnO-TiO2, the photocatalytic properties, research found that: NAC-FAS process synthesis of simple oxide nanocrystals , first, the-OH group-containing salt or hydroxide is formed, and then by dehydration - condensation reaction to form a solid phase precipitates, some of the larger size of the solid phase to achieve critical solid precipitate nucleation size; polycondensation reaction with dehydration - carried out, the solid phase core gradually grow up, this can be precipitated crystal phase or amorphous amorphous phase, wherein the amorphous phase with the continuation of the reaction time, the crystalline phase is formed by dissolution - precipitation \NAC-FAS process of ZnO nanocrystalline TiO2 nanocrystals and ZnO-TiO2 nanocrystals with good photocatalytic properties of TiO2 percent content of 42% -50% of ZnO-TiO2 nanocrystalline photocatalytic activity, by increasing the heat treatment The degree of crystallinity can improve the photocatalytic properties. The acidic environment can improve the nanocrystalline TiO2 and ZnO-TiO2 nanocrystalline photocatalytic performance the ZnO nanocrystalline TiO2 percentage of less than 50% ZnO-TiO2 nanocrystals easy to light corrosion.
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