TNTs电极光电协同降解磺胺类抗生素的研究  

Photo-electrocatalytic oxidation of sulfonamides by titanate nanotube electrodes

作　　者：陈梓慧 秦撼 杨鹏 鲁玥 姚硕 肖飞 陈慧英[1] 夏建新[1] 邢璇[1] CHEN Zihui;QIN Han;YANG Peng;LU Yue;YAO Shuo;XIAO Fei;CHEN Huiying;XIA Jianxin;XING Xuan(College of Life and Environmental Sciences,Minzu University of China,Beijing 100081,China;College of Chemistry and Environment,Hohhot Minzu College,Hohhot 100051,China;China Energy Conservation and Environmental Protection Group,Beijing 100082,China)

机构地区：[1]中央民族大学生命与环境科学学院,北京100081 [2]呼和浩特民族学院化学与环境学院,呼和浩特100051 [3]中国节能环保集团有限公司,北京100082

出　　处：《功能材料》2022年第12期12092-12099,共8页Journal of Functional Materials

基　　金：国家自然科学基金项目(51409285,51809087);中央高校基本科研业务经费项目(2021QNPY86);国家大学生创新训练计划项目(GCCX2020110034)。

摘　　要：利用水热法对Ti板进行处理制得钛酸盐纳米管(titanate nanotubes,TNTs)电极,并利用XRD,TEM和SEM对其进行系统表征,对比了TNTs电极在光催化,电催化和光电协同作用下对磺胺嘧啶(sulfadiazine,SD)的降解效果,探索了不同外加电压对降解效果的影响。结果表明,水热法成功制得内径为5 nm的无序排列的TNTs电极。在初始SD浓度80 mg/L,外加稳压5 V的条件下,TNTs电极在光电协同作用下对SD的降解效率较单纯光解或单纯电解均有提升,反应50 min降解率可达97.38%。在SD本身降解率较高的情况下,TOC去除率较低,这一结果表明溶液中存在大量SD降解中间产物。利用Gaussian软件在B3LYP/6-31+g(d,p)水平优化SD分子构象,结合密度泛函理论(density functional theory,DFT)计算福井函数和电子云密度,确定了SD分子中的反应活性位点,利用高效液相色谱串联质谱(liquid chromatograph mass spectrometer,LC-MS)对中间产物测定,检测到质荷比(m/z)为96、187、117等6种中间产物,推测了SD的两种降解途径。经探究,TNTs光电协同降解抗生素的性能优秀,对现今水体抗生素类污染降解有重大意义。Titanate nanotubes(TNTs)electrodes were produced by hydrothermal treatment of Ti plates and characterized by XRD,TEM and SEM,systematically.The effects of the applied voltage on the degradation effect were investigated.Results showed that the hydrothermal method was successful in producing disordered TNTs electrodes with an inner diameter of 5 nm.Under the conditions of an initial SD concentration of 80 mg/L and an applied voltage of 5 V,the degradation efficiency of the TNTs electrode under the synergistic effect of photo-electrolysis and electrolysis was improved compared with that of photolysis or electrolysis alone,with a degradation rate of 97.38%in 50 min.The low TOC removal rate in the presence of high SD degradation rate itself indicates that a large number of SD degradation intermediates are present in the solution.The reactive sites in the SD molecule were identified by optimizing the conformation of the SD molecule at the B3LYP/6-31+g(d,p)level using Gaussian software and calculating the Fukui function and electron cloud density in combination with density functional theory(DFT).The two degradation pathways of SD were postulated by combining the results of the intermediates determined by high performance liquid chromatography tandem mass spectrometry(LC-MS),which detected six intermediates with mass-to-charge ratios(m/z)of 96,187,117,etc.It was investigated that TNTs have excellent performance in degrading antibiotics and have significant implications for the degradation of antibiotic-like pollution in present-day water bodies.

关 键 词：钛酸盐纳米管电极 光电协同作用 纳米结构 磺胺嘧啶 降解机理 

分 类 号：X524[环境科学与工程—环境工程]