Synthesis And Characterization Of ZnO Nanocrystals Modified By PANI Or Ag And Their Photocatalytic Properties

Recently, semiconductor metal oxides (SMOs) have attracted much attention due to their potential applications in nanodevices,dye-sensitized solar cells (DSSCs),light emitting diodes,biomedicine,photocatalysis. Among various semiconductor materials, the wurtzite hexagonal structured ZnO has been extensively studied due to its easy synthesis,low price,innocuity,unique properties. However, pure ZnO used for photocatalyst has several drawbacks. Fox example, low photocatalytic efficency,photocorrosion,acid corrosion,low visible light activity. Therefore, with increasing environmental problems, it is very significative to develop modified ZnO composite photocatalysts for potential applications in waste water treatment.This paper focused on enhancing the photocatalytica property of ZnO nanomaterials, we took facile synthesis method to prepare ZnO composite photocatalysts modified by conjugated polymer and silver nanocrystal, respectively. The ZnO modified by PANI not only has visible light activity, but also has anti-photocorrosion property. In addition, studies on photocatalytic experiment of methylene blue optimized the prepared conditions and the photodegradation mechanism. The ZnO modified by silver nanocrystal show highly photocatalytic property, and the efficiency is much better than pure ZnO and commercial TiO₂ (P-25), so it is very propitious to organic waste water treatment.In this paper, we synthesized monolayer-PANI/ZnO composite photocatalysts and Ag/ZnO heterostructures assisted by UV light, and we took several scientific instruments such as XRD,TEM,FT-IR,XPS,PL and so on to characterize the products. The photocatalytic properties were measured by photodegradation of methylene blue (MB), and we discussed the influences of different PANI contents and different Ag contents on the photocatalytic property in details, we also introduced their interrelated mechanism. The photocatalytic results showed that the photocatalytic properties of as-synthesized photocatalysts were better than the pure ZnO, and the optimal content of PANI or Ag is very important to enhance the photocatalytic property.In all, we synthesized two different kinds of composite photocatalysts, one was conjugated polymer PANI modified ZnO, and the other was formation of heterostructures between ZnO and Ag. The photodegradation results indicated that the photocatalytic property of ZnO could be enhanced after compositing with other materials, we reached the aims. Furthermore, the research on photocatalytic materials paves the way for commercial applications in future and perfects the photocatalytic mechanism.