基于多孔二氧化钛-硒化镉量子点复合材料的光电化学传感器用于检测Hg^(2+)  

A Photoelectrochemical Sensor for Sensitive Detection of Hg^(2+) Based on M-TiO_(2)-CdSe Quantum Dots Composite Material

作　　者：欧盼盼 韦富存 吴叶宇 唐小强 陈智帆 吴佳雯 林瑜 谭学才 OU Pan-Pan;WEI Fu-Cun;WU Ye-Yu;TANG Xiao-Qiang;CHEN Zhi-Fan;WU Jia-Wen;LIN Yu;TAN Xue-Cai(Key Laboratory of Chemistry and Engineering of Forest Products,State Ethnic Affairs Commission,Guangxi Key Laboratory of Chemistry and Engineering of Forest Products,Guangxi Collaborative Innovation Center for Chemistry and Engineering of Forest Products,Key Laboratory of Guangxi Colleges and Universities for Food Safety and Pharmaceutical Analytical Chemistry,School of Chemistry and Chemical and Engineering,Guangxi University for Nationalities,Nanning 530008,China)

机构地区：[1]广西民族大学化学化工学院,林产化学与工程国家民委重点实验室,广西林产化学与工程重点实验室,广西林产化学与工程协同创新中心,广西高校食品安全与药物分析化学重点实验室,南宁530008

出　　处：《分析化学》2021年第11期1897-1907,共11页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(No.21365004);广西重点研发计划项目(No.桂科AB18126048);广西创新驱动发展专项资金项目(No.桂科AA18118013-10);广西科技基地和人才专项项目(No.桂科AD18126005);广西高校中青年教师科研基础能力提升项目(No.2019KY0162);广西民族大学研究生教育创新计划项目(No.gxun-chxps202077)资助

摘　　要：以多孔二氧化钛-硒化镉量子点(M-TiO_(2)-CdSe QDs)复合材料为基础,制备了一种新颖、简单的光电化学(PEC)传感器用于Hg^(2+)的超灵敏检测。采用场发射扫描电子显微镜(SEM)、高分辨率透射电子显微镜(HRTEM)、X射线粉末衍射仪(XRD)、X射线光电子能谱(XPS)、紫外-可见漫反射光谱(UV-Vis DRS)、光致发光(PL)光谱和红外光谱对材料的形貌和结构进行了表征,采用电流-时间法(i-t)和电化学阻抗谱技术(EIS)对传感器的性能进行了研究。结果表明,制备的M-TiO_(2)不仅保留了MIL-125(Ti)原有的形貌和结构,而且具有更丰富的孔结构和良好的性能。与M-TiO_(2)相比,M-TiO_(2)-CdSe QDs复合材料表现出优异的PEC性能,其光电流强度提高了2倍。基于Hg 2+对M-TiO_(2)-CdSe QDs PEC体系光电流强度的选择性抑制作用,构建了一种用于测定Hg^(2+)浓度的新型PEC传感器,其线性响应范围为0.005~5 nmol/L,检出限为4.2 pmol/L(S/N=3)。此传感器具有良好的选择性和较高的稳定性。对M-TiO_(2)-CdSe QDs PEC体系的检测机理进行了探讨。将传感器分别用于对邕江水、自来水以及桶装水进行分析,加标回收率在96%~110%之间。A novel and simple photoelectrochemical(PEC)sensor for ultrasensitive detection of mercury ion(Hg^(2+))was fabricated based on metal organic framework-derived porous titanium dioxide-cadmium selenide quantum dots(M-TiO_(2)-CdSe QDs)composites.The morphology and structure of different materials were characterized by field emission scanning electron microscopy(SEM),high resolution transmission electron microscopy(HRTEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS).The performance of the sensor was studied by current time method(i-t)and electrochemical impedance spectroscopy technology(EIS).The results showed that the prepared M-TiO_(2) not only retained the original morphology and structure of MIL-125(Ti),but also exhibited more abundant pore structure and good PEC properties.Comparing with M-TiO_(2),the as-prepared M-TiO_(2)-CdSe QDs nanocomposite exhibited excellent PEC performances including about 2-fold enhancement of photocurrent intensity,which were ascribed to the large surface of M-TiO_(2) and the introduction of CdSe QDs.Based on the selective inhibitory effect of Hg^(2+) on the photocurrent intensity of the M-TiO_(2)-CdSe QDs PEC system,a novel PEC sensor for Hg^(2+) concentration determination was constructed,with a wide linear response range of 0.005-5 nmol/L and a detection limit of 4.2 pmol/L(S/N=3).The detection method was used for analysis of Hg^(2+) in real water samples with the spiked recoveries of 96%-110%,and the possible detection mechanism of the M-TiO_(2)-CdSe QDs PEC system was also discussed.

关 键 词：光电化学传感器 金属有机框架衍生多孔二氧化钛 硒化镉量子点 汞离子 

分 类 号：O657[理学—分析化学] TB332[理学—化学] X832[一般工业技术—材料科学与工程]