Photocatalytic Properties Of Composite Materials Based On N-type Zinc Oxide And Bismuth Oxychloride

In recent years,with the acceleration of industrialization and urbanization in the world,people’s ability to use and transform nature has been strengthened,resulting in the depletion of various energy resources.At the same time,many untreated sewage will be discharged wantonly,so that a large number of water pollutants always threaten people’s health.Simultaneously,with the development of science and technology,the use of semiconductor photocatalytic technology for pollution purification has been widely concerned by the society,which can convert solar energy into chemical energy and has been as an efficient environmental protection way.The key factor of the photocatalytic degradation and reduction is photocatalyst.This paper will take semiconductor ZnO and BiOCl as the main research object to synthesize their respective composite semiconductor photocatalysts and study their photocatalytic properties.The main contents include:Three kinds of ZnO samples with different morphologies were prepared by hydrothermal method and chemical precipitation method using zinc nitrate,zinc acetate and sodium hydroxide respectively as raw materials.The ZnO samples were in the shape of thin flower,rod and coral flower,respectively.The obtained products were determined and analyzed by XRD SEM DRS and BET characterization methods.The photocatalytic properties of ZnO photocatalysts with three different morphologies were tested.It was found that the thin-flowered ZnO exhibited the best photocatalytic performance.The degradation rate of Rhodamine B was 95% after 280 min,and the reduction rate of Cr(Ⅵ)was 73.1% after 90 min.It shows that the microstructure and morphology of photocatalyst are important factors to determine the photocatalytic activity.Three kinds of ZnO/Zn S composites and thin flower-like ZnO/Ag composites were successfully prepared on the basis of three different morphologies of ZnO samples as substrates.The obtained products were determined and analyzed by XRD,SEM,DRS,BET and PL characterization methods.The photocatalytic degradation of rhodamine B and photocatalytic reduction of Cr(Ⅵ)were tested for each sample.The results show that among the three morphologies of ZnO/Zn S composites,the thin flower-like ZnO/Zn S sample showed the best photocatalytic degradation or reduction results.However,the thin-flower-like ZnO/Ag samples could degrade Rhodamine B completely in 90 minutes,and the degradation effect was the best among the four kinds of samples.It is shown that the photocatalytic efficiency can be improved by both semiconductor composite and precious metal deposition.The flake-like BiOCl and BiOCl/Cd S composites were prepared by hydrothermal method and water bath method.XRD,SEM,DRS,BET and PL characterization methods were used to determine and analyze the obtained products.The photocatalytic properties of each sample were tested.It was found that BiOCl/Cd S sample had excellent degradation performance towards Rhodamine B,and the degradation could be completed in 6 minutes.In the Cr(Ⅵ)reduction experiment,the reduction rate of BiOCl/Cd S sample has reached 99% within 60 min.It is proved that the semiconductor composite method can enhance the photocatalytic performance of the samples.