梯形异质结Bi2O3/BiOI的制备及降解四环素的机制研究  

Preparation of Bi2O3/BiOI step-scheme heterojunction photocatalyst and its degradation mechanism of tetracycline

作　　者：谭海燕 石新雨 程新华 吴德勇 江雪超 胡卫兵 TAN Haiyan;SHI Xinyu;CHENG Xinhua;WU Deyong;JIANG Xuechao;HU Weibing(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]超轻弹性体材料绿色制造国家民委重点实验室/湖北民族大学化学与环境工程学院,恩施445000 [2]广西民族大学广西林产化学与工程重点实验室,南宁530006 [3]武汉理工大学材料复合新技术国家重点实验室,武汉430070

出　　处：《华中农业大学学报》2021年第6期84-90,共7页Journal of Huazhong Agricultural University

基　　金：国家自然科学基金项目(21769009);超轻弹性体材料绿色制造国家民委重点实验室开放项目(PT092101);广西林产化学与工程重点实验室开放项目(GXFK1904);广西科技基地和人才专项(桂科AD 18126005);湖北省“双一流”建设专项;湖北民族大学博士启动基金(MY2018B022)。

摘　　要：以绿色焙烧方法制备梯形异质结复合材料Bi2O3/BiOI,将复合材料Bi2O3/BiOI用于抗生素生产废水中四环素的降解,并与纯的Bi2O3与BiOI的降解效果进行对比。以X射线衍射(XRD)、X射线光电子能谱(XPS)对Bi2O3/BiOI样品物相组成和形貌进行表征分析,采用分光光度法测试并计算Bi2O3/BiOI样品降解四环素,结果显示:降解率为92.4%,一级动力学常数为0.01859 min-1。密度泛函理论计算显示,Bi2O3与BiOI的功函数分别为3.0、6.0 eV。梯形异质结复合材料Bi2O3/BiOI在光催化反应时,在内建电场和能带弯曲的共同作用下,BiOI中导带上还原能力较弱的电子将与Bi2O3价带中氧化能力较弱的空穴部分复合,从而保留较强还原以及氧化能力的光生电子和空穴,这可能是梯形异质结复合材料Bi2O3/BiOI具有较高光催化活性的原因。Bi2O3/BiOI step-scheme heterojunction photocatalyst was synthesized with green calcination method and its degradation ability of tetracycline was investigated.The photocatalytic performance of the Bi2O3/BiOI heterojunction,Bi2O3 and BiOI was compared.The structure and morphology of the samples were characterized with X-ray diffraction(XRD),X-ray-photoelectron spectrograph(XPS).The degradation rate of tetracycline was analyzed with spectrophotometry.The result of calculation showed that the degradation rate of tetracycline was 92.4%in two hours.The first order kinetic rate constant was 0.01859 min-1.The result of calculation with density functional theory showed that the work function of Bi2O3 and BiOI was 3.0 eV and 6.0 eV,respectively.When this step-scheme heterojunction was used as a photocatalyst,the weaker electrons in the conduction band of BiOI were combined with the weaker holes in the Bi2O3 valence band under the combined effect with built-in electric field and band bending,retaining strong reducing and oxidizing ability of photoelectrons and holes,which may be the reason why Bi2O3/BiOI step-scheme heterojunction has higher photocatalytic activity.

关 键 词：梯形异质结 四环素 抗生素废水 光催化降解 电荷分离 光催化材料 铋系化合物 

分 类 号：O643[理学—物理化学]