基于有序大孔半导体氧化物的协同气敏性传感器的构建及其在VOCs检测中的应用研究

Semiconductor oxide gas sensors have promising application in monitoring and warning of volatile organic compounds (VOCs). Currently, the sensitivity of the fabricated gas sensors is low and in order to realize the high sensitive detection of VOCs, there is an urgent need for high-performance gas sensors. Ordered macroporous materials have the advantages of ordered porous structure, pore size adjustment and high special surface area, which make them have promising application in the improvement of sensing performance of gas sensor. This project will fabricate new-type gas sensor based on ordered macroporous semiconductor oxide, which will be used for high sensitive detection of VOCs. The surface character and conduction property of ordered macroporous semiconductor oxide will be tuned by pore structure, electronic structure and the loading of high dispersed precious metals in order to improve the detection sensitivity for formaldehyde, acetone and toluene. Investigate the synergy gas sensing property of precious metals and semiconductor oxide, and reveal the sensing mechanism of the atomically dispersed precious metals loaded semiconductor oxide on molecular level. The project will provide theory and technology basis for the property improvement of semiconductor oxide gas sensor and the high sensitive detection of VOCs.

半导体氧化物气体传感器在挥发性有机物（VOCs）的实时监测、预警方面具有广阔的应用前景。现有传感器灵敏度低，难以满足大气中VOCs的检测需求，迫切需要构建具有优异性能的半导体氧化物气体传感器。有序大孔材料具有孔道结构周期有序、孔径大小可调、比表面积大等优点，在改善传感器检测性能方面具有较大潜力。本项目将构建基于有序大孔半导体氧化物的新型气体传感器并用于VOCs的高灵敏度检测。通过孔结构、电子结构及贵金属的高分散负载调控有序大孔半导体氧化物的表面性质和传导性能，提高传感器对甲醛、丙酮及甲苯等气体的检测灵敏度。分析单原子贵金属负载型半导体氧化物对气体识别的分子机制，开展贵金属和半导体氧化物增强气敏性能的协同作用机理研究。项目的研究结果将为半导体氧化物气体传感器性能的改善及VOCs的高灵敏度检测提供理论和技术基础。

半导体氧化物气体传感器在气体污染物的实时监测、预警方面具有广阔的应用前景。大气中挥发性有机化合物浓度较低，通常在ppb级，为半导体氧化物气体传感器的检测灵敏度提出了新要求。本项目针对目前半导体氧化物气敏材料孔隙率低、传导性能差等原因导致所构筑的传感器对挥发性有机化合物检测灵敏度低的难题，开展了具有高晶化孔壁的三维有序大孔氧化钨、氧化锡、氧化铟等气敏材料的制备研究；利用高分散贵金属的负载进一步改善三维有序大孔氧化物气敏材料的检测性能。基于上述材料的气体传感器对三乙胺、低碳醇等气体的检出限达 ppt级。本项目还利用原位技术开展贵金属和半导体氧化物增强气敏性能的协同作用机理研究，分析单原子贵金属负载型半导体氧化物对气体识别的分子机制。相关研究成果发表在Angewandte Chemie International Edition，Applied Catalysis B: Environmental，ACS Sensors等期刊上发表，为半导体氧化物传感器性能的改善及气体污染物的高灵敏度检测提供理论和技术基础。