基于光催化燃料电池的卤代有机物自供能传感器研究

Self-powered electrochemical sensor is a new type of sensor based on construction of suitable cell system, in which the power for electrochemical sensing is provided by the electric energy generated from direct or indirect chemical reactions of analytes. So far, the researches concerning self-powered electrochemical sensors have been mostly based on enzymatic fuel cells. However, in such enzyme-based sensors, the analytes are limited by few categories of enzymes available. In the present project, we will employ photocatalysts to construct photocatalytic fuel cells based on the highly efficient catalytic degradation of organic pollutants over photocatalysts. By integrating the synergistic advantages of photocatalysis, cell and electrochemical sensing, a new type of self-powered environmental electrochemical sensor will be developed. The project will choose halogenated organic compounds (HOCs), a group of frequently detected pollutants with high toxicity, as the analytes. To construct the photocatalytic fuel cells for HOCs, three-dimensional carbon quantum dots composite photocatalytic electrodes possessing high catalytic activity under visible light illumination will be prepared. Then, molecular imprinting technique will be incorporated with composite photocatalysts to fabricate photoanodes with specific recognition ability toward various HOCs. Using such photoanodes, visible light photocatalytic fuel cells-based self-powered electrochemical sensors for HOCs will be systematically studied. Moreover, portable self-powered sensors for field measurements of HOCs will be fabricated. The research of this project will provide novel self-powered electrochemical sensors and expand the application of self-powered electrochemical sensors to environmental monitoring, thus having both academic research importance and value of practical application.

自供能电化学传感器，是通过构建合适的电池系统，利用待测物直接或间接参与化学反应产生电能，为电化学传感提供能源的新型传感器。目前国内外有关自供能电化学传感器的研究大多基于酶生物燃料电池，检测对象受酶催化剂种类局限。本申请项目拟利用光催化对有机污染物的高效催化降解作用，构建光催化燃料电池，综合光催化、电池和电化学传感的协同优势，用于发展新型自供能环境电化学传感器。项目拟选择在环境中危害大、检出率高的卤代有机物作为目标检测对象，在研制对可见光有高响应活性的碳量子点三维复合光催化电极的基础上，构建卤代物光催化燃料电池，并结合分子印迹技术研制对不同卤代物具有特异识别性能的光阳极，用于发展基于可见光催化燃料电池的自供能传感器，并研制适合野外现场使用的便携式自供能传感器。通过本项目的研究，对发展新型高性能自供能电化学传感器，拓展该类传感器应用范围至环境领域，具有重要的学术研究意义和实际应用价值。

传统的电化学传感器通常利用外加电源产生电信号，而自供能电化学传感器利用燃料电池的电输出提供检测信号，无需外加电源，具有设备更简单、易小型化等优势，有良好的发展应用前景；其中基于催化效率高、应用范围广、成本低、稳定性好的光催化材料构建的燃料电池为发展光引发的自供能传感器提供了基础。本项目按照预定研究计划，圆满地完成了全部研究任务，实现了预期研究目标，在研制了多种对可见光有高响应活性的复合光催化电极的基础上，设计构建了不同结构的光催化燃料电池，并结合分子印迹膜、适配体、酶等特异性识别元件，发展了灵敏度高、选择性好的自供能传感器，为3,3’,4,4’-四氯联苯(PCB77)、2,3',5,5'-四氯联苯(PCB72)、4-氯酚、2,4-二氯酚等卤代有机物以及其它污染物提供新型有效的传感检测方法，所取得的主要研究成果包括：设计了一种双室结构、可见光驱动的光催化燃料电池，成功地探讨论证其电输出作为检测信号用于发展自供能传感器；在此基础上又分别将分子印迹膜作为识别元件与p-型、n-型半导体光电极相结合，构建了基于光阳极型、光阴极型光催化燃料电池的自供能传感器；另外，将酶催化的氧化还原循环与光催化燃料电池相结合，分别利用酶催化的特异性和氧化还原循环来提高传感器的选择性和灵敏度；为了避免双室池不利于传感器微型化的缺点，又设计了一种无膜型单室光催化燃料电池，与适配体结合发展自供能传感器；为了避免检测过程中对于额外试剂的需求，还设计了一种无媒介剂的光催化燃料电池，构建自供能适配体传感器；在以上研究基础上，又进一步提出构建无媒介剂、无膜型的单室光催化燃料电池用于发展自供能传感器。另外，本项目还研制多种高性能可见光催化电极，用于污染物的光电化学检测和降解，这些研究都为本项目构建高性能光催化燃料电池以及发展能高灵敏、高选择性地检测污染物的传感器奠定了良好的基础。通过本项目研究构建高性能的光引发的自供能传感器，对于发展新型低成本的环境监测传感器有重要的学术意义和应用价值。