面向恶臭大气污染物H2S检测的高性能氧化物半导体气体传感器的研究

Hydrogen sulfide (H2S) is a highly toxic malodorous environmental pollution gas. It is of great significance to develop high-performance gas sensors for the rapidly accurate detection of H2S gas in the atmosphere. The project intends to construct high-performance H2S gas sensors based on semiconductor oxide nanomaterials through designing high-performance sensing materials, modification with functional materials and optimizing the structure of gas sensor. The synergistic sensitization effects of "micro-/nanostructure design of sensing materials", " surface modification of sensing materials " and “structure design of testing electrodes” will be applied to improve the sensitivity and selectivity of the gas sensors; The synergistic strategies of introducing anti-hygroscopic dopants and surface hydrophobic treatment will be used to enhance the anti-humidity properties of gas sensors; The activation treatment strategies with noble metals and UV/visible light will be applied to reduce the working temperature of the gas sensors, which is necessary to realize the safety detection of combustible H2S gas. To provide theoretical support for optimizing the sensing performance, the gas sensing mechanism as well as the effects of the strategies about improving the sensitivity, increasing the humidity resistance and reducing the working temperature will be investigated. Through the implementation of this project, it is not only expected to construct practical gas sensors for the detection of H2S pollutants, but also can provide new routes for the design of high-performance gas sensors based on semiconductor oxides.

硫化氢（H2S）是一种毒性极强的恶臭型环境污染气体，开发高性能的气体传感器对实现大气环境中H2S气体的快速准确检测具有重要意义。本项目拟从传感材料的设计制备、功能改性以及器件结构的优化出发，构建基于氧化物半导体纳米传感材料的高性能H2S气体传感器。通过融合“材料结构增感”、“材料改性增感”和测试电极的“结构增感”三级增感策略，提高传感器的灵敏度和选择性；通过抗湿性杂质掺杂和传感材料表面疏水化处理的协同抗湿策略，增强传感器的耐湿性；通过贵金属活化和紫外/可见光活化的协同作用降低传感器的工作温度，从而实现对大气环境中易燃性H2S气体的安全准确检测；系统研究上述增感、抗湿以及降低工作温度策略对传感器性能的调控规律与作用机理，为传感器性能的优化提供理论支撑。本项目的实施不仅有助于构建面向大气污染物H2S气体检测的实用化传感器件，也能为高性能氧化物半导体气体传感器的设计提供新的思路。

气体传感器在监测易燃易爆、有毒有害气体方面发挥着重要作用。本项目以构建高灵敏度、高选择性、且工作温度低的氧化物半导体型气体传感器为目标，从敏感材料制备、组成/缺陷调控、表面修饰改性以及室温传感器设计方面分阶段系统地开展了研究工作。.1.敏感材料化学组分调控与气敏性能优化：利用静电纺丝和原子层沉积(ALD)技术相结合，实现了异质结材料（CuO/ZnO）化学组分的精确调控。当异质结材料中ZnO和CuO的结合比例为15.6时，传感器对100 ppm H2S的灵敏度达到了60.5，相比于纯相ZnO和CuO提高了6和45倍。.2.敏感材料结构缺陷调控与气敏性能优化：通过控制Sn掺杂浓度，有效调控了In2O3材料内部结构缺陷（杂质和空位）的数量，进而提升了材料表面的载流子浓度和活性位点数量。获得的Sn掺杂In2O3与纯In2O3相比，灵敏度提高了3.4倍。.3.敏感材料表面修饰改性：利用表面修饰改性技术，调控复合材料ZnO/ZnFe2O4/Au界面处的空间耗尽层宽度和表面处的气体吸附，改善了敏感材料的选择性和灵敏度。与未经表面修饰的ZnO相比，ZnO/ZnFe2O4/Au复合材料的灵敏度提高了5.5倍，且选择性也有显著提升。.4.室温气体传感器构筑：以紫外/可见光作为传感器新的驱动方式，发展了光驱动的室温气体传感器。利用光生电子和空穴的还原和氧化能力，活化敏感材料表面的气体吸/脱附和反应过程，在室温下实现了对NO2、H2S等气体的高灵敏检测。. 项目取得的研究结果，为研发高性能氧化物半导体敏感材料提供了技术参考，为设计构筑新型的室温高性能气体传感器提供了新的思路。