| Organic dye as an indispensable raw material in industry and life, is widely used in food, pharmaceutical, printing and cosmetic industries. However,the emission of organic dyes will not only destroy the ecological balance of the environment, but also take a serious threat to people’s health. In China, there are many dye industries and dyeing industrial enterprises. Controlling organic dyes pollution is urgent. There are a lot of processing technologies for organic dyes, such as ozone oxidation, iron carbon reduction, photocatalytic method, etc.Photocatalytic method has a simple structure and is easy to control operating conditions.Also it has strong oxidizing ability. Degradation of the organic dye in air and water in Photocatalyst and converting them into less harmful chemicals have attracted more and more attention. There are a lot of researches about the preparation of photocatalyst. However, cerium oxide and graphene composite materials research is relatively less. It has a lot of cerium oxide and graphene research in the field of photocatalysis. In this study, CeO2nanowires-reduced graphene oxide hybrids (CeO2NWs-RGO) were synthesized by a green hydrothermal method using CeO2NWs and graphene oxide (GO) as raw materials.Graphene is a2-dimensional, crystaline allotrope of carbon. It has excellent electrical properties.It is a zero bandgap semiconductor material and has a unique carrier features. Also it has excellent transmission characteristics to the photo-generated electrons in catalyst. Graphene oxide which is prepared in the experiment is reduced Preparation method is simple and we can realize large-scale synthesis. With the change of the ambient oxygen partial pressure and temperature the oxygen vacancies can form in fluorite structure of ceria (CeO2). Because of this,ceria (CeO2) has excellent characteristics of oxygen storage and release. Moreover, CeO2can be considered as an n-type semiconductor with a wide band gap of2.9-3.2eV, and it has some properties like commonly used photocatalyst TiO2such as nontoxicity, high stability and strong absorption in the UV region.In terms of excellent properties of graphene and cerium oxide, we prepare a novel photocatalyst.This article is divided into the following contents.(1) Graphene oxide can be prepared with a modified Hummers method.We finished the reduction of graphene oxide followed by hydrothermal method. Graphene oxide and reduced graphene oxide are analyzed by XRD, SEM, XPS, FTIR and Raman.(2) CeO2nanowires were synthesized by hydrothermal method and characterized by using XRD,SEM and TEM.The results of researches showed that good conditions were0.08mol/L cerium chloride as cerium source,10mol/L sodium hydroxide as a precipitating agent and the hydrothermal temperature of180℃. The nanowires we get finally are high purity, uniform particle size and single good dispersion.(3)CeO2nanowires-reduced graphene oxide hybrids (CeO2NWs-RGO) as photocatalyst were synthesized by a green hydrothermal method using CeO2NWs and graphene oxide (GO) as raw materials. It is investigated that the degree of photocatalytic activity for the degradation of Rhodamine B (RhB) as a model pollutant under UV-light irradiation. The test results showed that the degree of photocatalytic activity is best with the mass ratio of RGO in the hybrids which is8.0wt%(the loading amount of RGO is respectively0,0.5,1.0,2.0,4.0,6.0,8.0wt%).But the photocatalytic effect is inhibited when the loading amount of RGO exceeds10wt%.We attribute this lower activity to the lower excitation effciency of CeO2in the hybrid due to the increased absorbance or scattering of irradiation through excess RGO in the reaction solution. |
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