| In recent years, ZnO nanorod array has been extensively studied as an ideal loaded photocatalytic system, due to its high specific surface area, light capture efficiency and photoelectron transfer ability. However, the shortcomings of its low quantum efficiency, wide band gap, as well as easy to light corrosion has hindered its practical application. Therefore, it is of great importance to develop the supported ZnO photocatalyst with high stability, high efficiency, and high sensitivity to visible light. Recent researches have revealed that the localized surface palsmon resonance effect based on noble metal nanoparticles(Au, Ag, Pt, etc.) can effectively improve the photocatalytic activity of semiconductors with wide band gap. Meanwhile, surface palsmon resonance effect is expected to enhance the visible light sensitivity for semiconductors with wide band gap. Currently, it lacks of researches about precious metal type, surface topography and the type of the silver halide photocatalytic activity of surface modified supported ZnO based on the surface palsmon resonance effect. Therefore, Based on the preparation of ZnO nanorod arrays films, the preparation and photocatalytic activity of Au, Ag and Ag X(Ag I, Ag Br) surface modified ZnO nanorod arrays were studied in this thesis. It discussed the reaction mechanism about loaded surface plasmon photocatalyst, which has a strong practical significance the development of that.The main results and innovations are displayed as follows:(1)Based on the photocorrosion mechanism of ZnO, it discussed the causes of vertical optical corrosion cracks of ZnO nanorods, and analyzed the photocatalytic activity and photostability mechanism, as a result of the coupling of surface effects of arrays and surface plasmon resonance effect of Au nanoparticles. Due to the internal electric field of ZnO, electrons and holes occur longitudinal separation during the photocatalytic process, and continuous migration of holes along the [0001-] direction eventually lead to longitudinal cracks. The research showed that Au nanoparticles modification can improve ZnO nanorods photocorrosion. surface plasmon resonance effect can improve the electron capture capability of Au and change the separation path of the light-generated electrons and holes, thereby improving the photostability of ZnO nanorod arrays.(2)It has found that the different morphologies modification of Ag affect photocatalytic activity of ZnO. Ag nanosheets have large surface area, which can effective transfer photogenerated electrons and exhibits excellent UV-visible photocatalytic activity; Ag nanoparticles have surface palsmon resonance effect, which can excited Ag generate electrons and injected into the conduction band of ZnO under visible ligjt irradiation to obtain visible light activity.(3)Based on the surface plasmon resonance effect of Ag/Ag Br, it was incorporated on the surface of ZnO nanorod array to develop the surface plasmon photocatalyst. It has shown that Ag/Ag Br modified ZnO exhibits excellent visible light photocatalytic activity and stability. On the one hand, surface palsmon resonance of Ag nanoparticles can increase the absorption of visible light of Ag/Ag Br/ZnO nanocomposite structure and improve electron trapping capability; On the other hand, surface plasmon resonance effect may excited Ag nanoparticles to generate electron-hole pairs under visible light irradiation, and transferred electrons to ZnO conduction band, resulting in the improvement of visible photocatalytic activity. |
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