| In the recent years,there was a common understanding that support affected the catalytic activity significantly.However,the element of support effect was not clarity. In this dissertation,the author investigated different crystal form of TiO2 as support, introduced Zn2+ into TiO2, TiO2 were treated at different temperature,and the effect of chloride on supported Au catalysts.Supported Au/TiO2 catalysts were prepared by deposition-precipitation(DP) method and characterized by diffuse reflectance spectroscopy(DRS),X-ray photoelectron spectroscopy(XPS), and transmission electron microscopy(TEM), etc. Then their photocatalytic performance of ozone were evaluated. The DRS of Au/TiO2 exhibited a band around 550 nm. This band was characteristic peak for the plasmon resonance of metallic gold nanoparticles. So the author concluded that the Au clusters were metallic state, which was consistent with the XPS results. And the binding energy of Au 4f XPS spectra showed that the Au clusters acted as the electron trap center. The Au/TiO2 photocatalysts were prepared by the deposition-precipitation method with different crystal form of TiO2 as support. The influence of crystall form of TiO2 on photocatalytic decomposition of gaseous ozone over Au/TiO2 was studied. The results showed that the orders of the photocatalytic activity of different crystal form of TiO2 support are as follows: Au/P25>Au/ anatase>Au/rutile, which is in accord with the orders of the photocatalytic activity of pure TiO2. Besides, the photocatalytic activity of TiO2 increased significantly by loaded Au. As well as the different activity of the support to decompose ozone,the results of Au 4f XPS showed that three crystal form of TiO2 have obviously different ability of change transfer from TiO2 to Au cluster. The synergistic effects was responsible for the different activity of Au/TiO2. At the same time, the results of SPS singnals were consistent with photocatalytic activity: the stronger the SPS singnals, the larger the separation rate of photoinduced electron-hole pairs, the higher the photocatalytic activity.Based on the important effect of tio2-based support to photocatalytic decomposition of ozone ,in this paper, composite oxide TiO2/ZnO with Ti/Zn mol ratio of 2:98 had been prepared by incipient-wetness impregnation(IMP), co-precipitation(CP), and Hydrothermal(HYD) and had been accomplished gold catalysts by DP method.Then their photocatalytic activity for ozone were compared with Au/TiO2.The results showed that the catalytic activity of Au/ TiO2/ZnO lower than that of Au/TiO2.The reasons may be as follows:first,besides the Au on the TiO2-ZnO(IMP) treated in air at 473 K for 4 h were metal state,the state of Au on the both TiO2-ZnO(CP) and TiO2-ZnO(HYD) were oxidized; second, the introduced Zn2+ replaced Ti3+ partially which lead to the active site of catalysts have decreased.The pretreatment temperature of TiO2 affected the catalytic activity of the supported gold catalysts significantly.In this paper,the TiO2 were treated at 200℃, 500℃,750℃,850℃,1000℃in air for 4 h,respectively.Then their photocatalytic activity for ozone were evaluated.The results indicated that the TiO2 both untreated and pretreated at 200℃had poor phocatalytic activity,and the activity was drop-off.Then the TiO2 pretreated at 500℃had the optimum activity.when the temperature increased to1000℃,the activity of TiO2 is almost inexistence. Finally,the author investigated that the effect of chloride on supported Au catalysts.The results showed that the photocatalytic decomposition of ozone on Au catalysts had increased significantly by removed chloride with distilled water washing. There was no significant change at the TEM pictures of Au clusters between washed and unwashed.The content of chloride characterized by XPS showed washing by distilled water was effective in removing chloride from the catalysts.
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