半导体光催化氧化技术在处理能源危机和环境污染问题方面有非常重要的应用.选取石墨烯对水热法制备的Zn2SnO4进行改性.通过透射电镜(T EM)观察其形貌特征,通过X射线衍射(XRD)、红外光谱(FT IR)、拉曼光谱(Raman)以及X射线光电子能谱(XPS)分析其结构和组成.采用紫外-可见光分光光度计检测石墨烯/Zn2SnO4催化降解亚甲基蓝(MB)性能.通过添加自由基捕获剂的光催化实验、电子顺磁共振谱和荧光光谱检测分析石墨烯/Zn2SnO4降解MB的光催化机理.通过光催化重复性实验对石墨烯/Zn2SnO4的稳定性进行评估.结果表明:加入石墨烯不会对Zn2SnO4的结构形貌产生较大影响;当氧化石墨烯(GO)添加量为4 Wt% 时,石墨烯/Zn2SnO4的光催化活性最高的;光催化过程中·OH是主要的活性物质,存在·OH间接氧化有机污染物的机制.%Semiconductor photocatalytic oxidation technology has a very wide application in dealing with energy crisis and envi-ronmental pollution problems.In this paper,the grapheme was used to modify Zn2SnO4prepared by hydrothermal method.The structure characteristics of grapheme/Zn2SnO4were investigated by X-ray diffraction(XRD),Infrared spectroscopy(FT-IR) and Raman spectroscopy.The transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy were used to ob-serve its morphology and analyze chemical composition,respectively.The photocatalytic performance of graphene/Zn2SnO4pho-tocatalytic degradation of methylene blue(MB)under UV irradiation was investigated by UV-Vis spectrophotometer.The pho-tocatalytic mechanism of degradation of MB was dicussed by photocatalytic experiment with free radical scavenger,electron para-magnetic resonance spectrum and fluorescence spectrum.The stability of the photocatalyst was evaluatedby repetitive photocata-lytic experiments.The results showed that the addition of graphene had no influence on the structure and morphology of Zn2SnO4.And when the additive amount of Graphene oxide(GO)is 4Wt%,the grapheme/Zn2SnO4can exhibited the highest photocatalytic activity.During the photocatalytic process,·OH was the dominant photooxidant,and there was indirect reaction between ·OH and organic chemical dyes.
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