多氯联苯光电化学还原型传感器的构筑与高灵敏高选择性响应机制

项目名称： 多氯联苯光电化学还原型传感器的构筑与高灵敏高选择性响应机制

项目编号： No.21307091

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 环境科学、安全科学

项目作者： 史慧杰

作者单位： 同济大学

项目金额： 25万元

中文摘要： 本项目针对多氯联苯（PCBs）在环境中浓度很低、单体众多、背景介质复杂，难以实现高灵敏、高选择性的实时、快速分析的难题，和PCBs化学结构极其稳定、抗氧化能力强的特点，通过构筑具有高效光电催化活性的Pd QDs/{010}TiO2/BDD电极，实现PCBs单体(PCB118)的快速、完全、光电协同催化还原脱氯，进而实现PCBs单体的高灵敏催化还原型光电化学分析的研究思路。通过电极表面微观结构设计和选择性功能化，采用双模板分子印迹技术在光催化剂{010}TiO2表面构筑分子识别能力高度专一的分子印迹位点，提高目标PCBs单体在电极表面的选择性吸附能力，解决光电化学传感器选择性低的问题。采用光电化学研究方法，并结合离子色谱、气相色谱等技术对PCBs在传感器表面的光电协同催化还原脱氯机制进行研究；结合实验及理论计算的方法构建分子印迹位点与模板分子间相互作用的理论模型，探讨传感器的选择性识别机制。

中文关键词： 多氯联苯；光电化学还原；分子印迹；高灵敏；高选择性光电化学传感

英文摘要： Owing to the low concentration of polychlorinated biphenyls (PCBs) in the environment, numerous congeners and complex matrix, it is hard to achieve the fast, real-time, highly sensitive and selective detection of PCBs. In this project, an photoelectrochemical reduction based PCBs sensor is proposed based on the fast and complete dechlorination of PCB congener (PCB118) on Pd QDs/{010}TiO2 /BDD with highly efficient photoelectrochemical reducibility, considering the stable chemical structure of PCBs and their resistance to oxidation. In order to conquer the limitation of low selectivity of photoelectrochemical sensor, a special dual-template molecular imprinting technique is employed to fabricate recognition sites directly on {010}TiO2, so that highly selective and specific adsorption of the template PCB congener will be obtained. The fast and complete dechlorination of PCB congener as well as its mechanism of the photoelectrochemical synergetic catalysis will be investigated in detail by photoelectrochemical method combined with ion chromatography and gas chromatography. Suitable theoretical models will also be constructed to mimic the interactions between the template PCB congener molecule and the imprinting matrix, and the high selectivity of the sensor will be discussed experimentally and theoretically.

英文关键词： polychlorinated biphenyls；photoelctrochemical reduction；molecular imprinting；high sensitivity；highly selective photoelectrochemical sensor