Preparation And Photocatalytic Performances Of Several Kinds Of Zn-based Photocatalytic Materials

Photocatalytic technology, a new type of waster water treatment and air purification, has the advantages of green, stable and efficient, and thus has potential application prospect in control environmental pollution. Zn-based photocatalysts is an important semiconductor photocatalytic material. However, there there also have many problems in the preparation process of Zn-based photocatalysts and its practical application, such as the preparation process is complex and low efficiency,and the Zn-based photocatalysts is difficult to be separated from the reactants and recycled and also low efficiency in the application of photocatalytic and so on. This paper is based on previous researches, aimimg at improving and optimizing the existing shortcomings in the preparation of Zn-based photocatalysts. In addition, by means of loading, in order to facilitate the Zn-based photocatalysts to be separated from the reactants and recycled.The main research contents and results are as follows:1. The nanometer Zn WO4 photocatalysts were successfully prepared, using Na2WO4·2H2O and Zn(NO3)2·6H2O as raw materials, by a ball milling induced solid-state reaction technology. The phase composition and particulate morphology of as-prepared samples were characterized by X-ray diffraction(XRD) and transmission electron microscopy(TEM) techniques. The influence of ball grinding conditions on the composition and structure of products was systematically studied,and the photocatalytic activity of as-prepared Zn WO4 photocatalyst was evaluated through the photodegradation of methyl orange(MO) under UV light irradiation. The photocatalytic experimental results showed that the prepared Zn WO4 has the photocatalytic performance for the degradation of MO, and the photocatalytic degradation rate of MO can reach 91% within 3 h irradiation.2. The nanometer Zn WO4/Bi2WO6 photocatalysts were successfully prepared,using Na2WO4·2H2O, Bi(NO3)3·5H2O and Zn(NO3)2·6H2O as raw materials, by a ball milling induced solid-state reaction technology. The phase composition and particulate morphology of as-prepared samples were characterized by XRD and TEM, TEM-mapping techniques. The influence of ball grinding conditions on the composition and structure of products was systematically studied, and the photocatalytic activity of as-prepared Zn WO4/Bi2WO6 photocatalyst was evaluated through the photodegradation of MO under visible light irradiation. The photocatalytic experimental results showed that Zn WO4/Bi2WO6 photocatalytic activity was significantly higher than that of a single Zn WO4 and Bi2WO6, and the photocatalytic degradation rate of MO can reach 96% within 1.5 h irradiation.3. Zn S-Sn S2 composite photocatalyst was prepared by one-pot hydrothermal method using Sn Cl4.4H2O、Zn SO4.7H2 O and thiourea as raw materials. XRD and TEM were used to characterize the phase composition and morphology of the products, and the effects of hydrothermal conditions on the products were investigated. The photocatalytic activity of synthetic products was evaluated by the photocatalytic decoloration of MO aqueous solution. Experimental results showed that the photocatalytic degradation efficiency of the as-synthesed Zn S-Sn S2 composites was obviously superior to that of single Zn S or Sn S2. The Zn S-Sn S2 synthesed at 160 ℃ for 8 h had the highest photocatalytic activity, and the decolorization percentage of methyl orange reached 89% after visible light irradiation for 3h.4. Using glucose and Fe3O4 as the raw materials synthesis Fe3O4@C complex,then using the ethylene glycol as solvent, the Fe3O4@C complex as the carrier,Cu Cl2·2H2O, Sn Cl4·4H2O, Zn SO4·7H2O, and CS(NH2)2 as raw materials,Fe3O4@C@Cu2Zn Sn S4 composite photocatalyst was prepared. XRD and TEM were used to characterize the phase composition and morphology of the products.We also explore the effects of different dosage of solvent, reaction time, reaction temperature on preparation of Fe3O4@C@Cu2Zn Sn S4 nanocomposite system.