基于富硫缺陷MoS2异质柱撑结构对ppb级NO2的室温传感机制研究

基于国家超低排放的战略需求，急需针对ppb级NO2发展安全、便捷的高性能半导体室温传感技术。MoS2对NO2吸附能高且具备噪声低及室温载流子迁移率高等优势，是理想的ppb级NO2室温敏感材料。然而，现有MoS2基室温传感器对ppb级NO2灵敏度、响应速率和恢复性能均不足。为解决此难题，本项目提出构筑富硫缺陷MoS2基异质柱撑结构，减少MoS2的堆垛、团聚，促进表面活性位点暴露，强化NO2吸附以提升室温灵敏度；进而利用硫缺陷的“电子陷阱”功能提升光生电子-空穴分离效率，实现光照与硫缺陷协同强化自由电子转移及NO2脱附以增强室温响应速率和恢复性能；结合结构、性能表征和原位分析手段揭示敏感材料的制备规律及其NO2室温传感机制与构效关系，以望实现对ppb级NO2的室温高灵敏、快速可恢复传感。本项目的实施有望为气敏材料的设计和低浓度有毒有害气体的室温传感技术提供有效新途径和理论支撑。

Based on the strategic demand of ultra-low emission in China, it is urgent to develop safe and convenient high-performance semiconductor room temperature sensing technology for ppb level NO2. MoS2 is an ideal room temperature sensing material for ppb level NO2 owing to its advantages of high adsorption energy for NO2, low noise and high carrier mobility at room temperature. However, the sensitivity, response rate and recovery performance of MoS2 based room temperature sensors for ppb level NO2 are still insufficient. To solve the problems, this project plans to construct sulfur vacancy-enriched MoS2 based heterogeneous pillared structure, so as to reduce the stacking and agglomeration of MoS2, leading to the effective exposure of surface active sites for enhanced NO2 adsorption to enhance the sensitivity at room temperature. In addition, the "electron trap" function of sulfur vacancy can be used to enhance the efficiency of photogenerated electron-hole separation, so the synergistic effects of light and sulfur vacancy can be used to enhance the free electron transfer and NO2 desorption, leading to the improved room temperature response rate and recovery performance. Furthermore, combined with the structure, property characterization and in-situ analysis, the preparation rules of the sensing materials, the room temperature sensing mechanism and structure-activity relationship will be revealed, thus promoting the development of MoS2 sensor with high sensitivity, rapid sensing rate and reversible to ppb level NO2 at room temperature. This project is expected to provide effective routes and basic data for the design of sensing materials and the room temperature sensing technology of low concentration toxic and harmful gases.