Preparation of Bi_(2)O_(3)/BiOI Step-scheme Heterojunction Photocatalysts and Their Degradation Mechanism of Methylene Blue  

作　　者：JIANG Xuechao TAN Haiyan SHI Xinyu CHENG Xinhua HU Weibing HU Xinhui 姜雪超;谭海燕;SHI Xinyu;CHENG Xinhua;HU Weibing;HU Xinhui(Key Laboratory of Green Manufacturing of Super-light Elastomer Materials of State Ethnic Affairs Commission,School of Chemistry and Environmental Engineering,Hubei Minzu University,Enshi,445000,China;Guangxi Key Laboratory of Chemistry and Engineering of Forest Products,Guangxi University for Nationalities,Nanning,530006,China;State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan,430070,China)

机构地区：[1]Key Laboratory of Green Manufacturing of Super-light Elastomer Materials of State Ethnic Affairs Commission,School of Chemistry and Environmental Engineering,Hubei Minzu University,Enshi,445000,China [2]Guangxi Key Laboratory of Chemistry and Engineering of Forest Products,Guangxi University for Nationalities,Nanning,530006,China [3]State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan,430070,China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2022年第5期801-806,共6页武汉理工大学学报（材料科学英文版）

基　　金：Funded by National Natural Science Foundation of China (No.21769009);Project of Innovation and Entrepreneurship for College Students in Hubei Minzu University (No.S202010517044);The foundation of Key Laboratory of Green Manufacturing of Super-light Elastomer Materials of State Ethnic Affairs Commission.(Hubei Minzu University)(No.PT092101);The Open Project of Guangxi Key Laboratory of Chemistry and Engineering of Forest Products(No.GXFK1904);Specific Research Project of Guangxi for Research Bases and Talents(No.AD18126005)。

摘　　要：Bi_(2)O_(3)/BiOI step-scheme(S-scheme) heterojunction photocatalyst was synthesized by green calcination method, its degradation ability of methylene blue was investigated, and the photocatalytic performance of the Bi_(2)O_(3)/BiOI heterojunction, Bi_(2)O_(3) and BiOI was compared. The structure and morphology of the samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), and UV-vis diffuse reflection spectrum (UV-vis DRS). The degradation rate of methylene blue was analysised by spectrophotometry, and the calculation result showed that the degradation rate of methylene blue was 97.8% in 150 minutes. The first order kinetic rate constant of 10%Bi_(2)O_(3)/BiOI is 0.021 8 min^(-1), which are2.37 and 2.68 times of BiOI(0.009 18 min^(-1)) and Bi_(2)O_(3) (0.008 03 min^(-1)) respectively. The calculation result shows that the work function of Bi_(2)O_(3) and BiOI are 3.0 e V and 6.0 e V, respectively, by density functional theory(DFT). When this S-scheme heterojunction is used as a photocatalyst, the weaker electrons in the conduction band of BiOI will be combined with the weaker holes in the Bi_(2)O_(3) valence band under combined effect with built-in electric field and band bending, which will retain stronger photoelectrons and holes between Bi_(2)O_(3) and BiOI. This may be the internal reason for the efficient degradation of tetracycline by Bi_(2)O_(3)/BiOI S-scheme heterostructures.

关 键 词：step-scheme heterojunction methylene blue antibiotic wastewater treatment photocatalytic degradation charge separation 

分 类 号：O643.36[理学—物理化学] O644.1[理学—化学] X703[环境科学与工程—环境工程]