Synthesis, Characterization And Photocatalytic Performance Of The High Efficiency And Wide Response Photocatalysts

Energy and environment problems are the two major challenges of global common facing nowadays. As the tempting prospects of semiconductor photocatalysis in solving energy and environment problem, it quickly became a research focus at home and abroad. At present, the synthesis and regulate of new catalyst and explore the potential mechanism of photocatalytic has got more and more attention. This paper is by these photocatalytic activity basic units: ZnWO4, CaWO4, plasma photocatalytic Ag-AgBr, and nanometer Ag, then through the composite and surface modification method to improve the photocatalytic activity、stability, and expand the light response of the photocatalyst; Use dyes and drugs as research target pollution, and discuss the degradation mechanism, in order to solve design new type of high efficient photocatalyst, provides the theory basis for repair of environmental pollution. The main research results of this paper are as follows:(1) By the chemical precipitation-deposition and the photochemical reduction method to compose the new type of nanorods which also has visible light response of the target catalyst. The new synthesis catalyst did a series of characterization: SEM、DRS、XRD、TOC、BET、 Zeta potential、XPS and so on. The result shows that the Ag-AgBr has successfully loaded on the nanorods. In the visible light (400nm) area, we researched the degradation of azo dye acid scarlet (AR18) optical activity, and the results indicated that the catalyst has the perfect photocatalytic stability and activity. Also do the different influence factors such as:dye concentration, catalyst dosage, pH value, the loaded amount of Ag and so on. By doing inhibition test and analysis of the relationship between the valence band, showed that the degradation of azo dye is a major role in the process of the plasmon resonance effect of Ag and cavitation oxidation. Finally we put forward and draw the photocatalyst degradation mechanism and path.(2) In this chapter, through the reduction method to make nano Ag successfully load on the nanorods ZnWO4. We also did a series of characterization: SEM、DRS、XRD、TOC、 BET、Zeta potential、XPS and so on. The result shows that the Ag has successfully loaded on the nanorods. With the target degradation of Rhodamine B, photodegradation experiments indicate that it has perfect stability and activity. At the same time, we also made several influence factors of contrast experiment: pH, catalyst dosage, concentration of dye, Ag load, etc. Finally, Zeta potential and impedance spectroscopy measurement done some research on its mechanism and discussed.(3) In this part we mainly do the visible light response type composite photocatalyst Ag-AgBr/CaWO4to depredate the antibiotics (Ofloxacin), also about its research and discussion. Catalyst Ag-AgBr/CaW04concentration, solution pH, the dosage of antibiotics and other several influence factors were analyzed. Also did the optical activity of Fe3+, H2O2, pH value and the three factors of the influence of the response surface optimization experiment; last we get the optimum experimental conditions.