分级结构p-金属氧化物半导体/n-Zn2SnO4纳米复合材料的可控制备与气敏性能研究

Metal oxide semiconductor (MOS) based gas sensor plays an important role in the filed of environmental gas detecting. With the increasing demands of MOS sensor in practical application, developing new sensor materials with high performance will be of great important. Therefore, in this project, we will put our focuses on the controllable synthesis and gas sensing properties of hierarchical nanostructures of Zn2SnO4 decorated with p-MOS(CuO,NiO, or Cr2O3) nanostructures. Hierarchical Zn2SnO4 nanostructures will be prepared by low-temperature wet chemistry synthesis method. Then the prepared hierarchical Zn2SnO4 will be decorated by p-MOS through thermal treatment method and solution self-assembly method, respectively. In order to develop the controllable synthesis method for p-MOS/n-Zn2SnO4 nanocomposites, the nucleation, crystal growth, and assembly mechanism of hierarchical structures of Zn2SnO4 and p-MOS , as well as the influence of experimental conditions on the formation of various products will be carried out. Furthermore, in order to understand the gas sensing mechanism, the factors that can affect the gas sensing properties will be also investigated, such as the p-n heterojuctions and the morphology, size and dispersion of assembly units. We will achieve some important results on the controllable synthesis and gas sensing properties of hierarchically structured p-MOS/n-Zn2SnO4 nanocomposites, and then pave the way for their future application in gas sensors.

金属氧化物半导体(MOS)气体传感器在气体检测领域占有重要地位。发展高性能气敏材料对提高传感器性能以满足实际需要具有重要意义。本项目拟开展分级结构p-MOS(CuO、NiO或Cr2O3)/n-Zn2SnO4的可控制备及气敏性能研究工作。采用低温液相合成方法制备分级结构Zn2SnO4，再通过金属盐热处理或液相自组装方法对其进行表面修饰，制备分级结构p-MOS/n-Zn2SnO4纳米复合材料。探索不同介质中分级结构Zn2SnO4及p-MOS纳米单元的成核、生长及组装机理，获得p-MOS/n-Zn2SnO4在组分和组装结构上的可控制备方法；重点研究p-n结、组装单元形貌、尺寸及分散行为等对气敏性能影响的规律，理解其气敏机制。本项目的实施，将在p-n型MOS/Zn2SnO4分级结构纳米复合材料的可控制备及气敏性能研究方面取得重要成果，为该类材料在气体传感器领域的应用打下坚实基础。

新型高效氧化物半导体纳米气敏材料的设计与制备是气体传感领域的研究重点。本项目系统开展了分级结构p-金属氧化物半导体/n-Zn2SnO4复合材料的可控制备与气敏性能研究工作，发展了多级多孔结构NiO/SnO2/Zn2SnO4、石墨烯/Zn2SnO4、NiO/SnO2的可控制备方法，并对通过XRD、SEM、TEM、N2-sorption，TG-DSC等方法所合成材料进行详细的表征。系统测试了所得制备材料的气敏性能，重点研究了材料组分、结构、微观形貌以及p-n结对材料气敏性能（灵敏度、选择性、工作温度、响应-恢复特性、重复性和稳定性等）的影响，深入分析了材料的气体敏感机理及异质结对材料的增敏机理。研究结果证明，通过敏感材料自身结构的优化，提高敏感材料的表面利用率，是获得高气敏性能的一种可行方法；此外，在n-MOS纳米材料中适量引入p-型半导体构筑p-n型异质结构纳米复合材料，利用异质结对敏感材料表面空间电荷层厚度的调控，可以获得更加优异的气敏性能。本项目的研究不仅为新型p-n型多级多孔氧化物半导体纳米材料的可控制备提供了可行的实验方法，同时也为高性能MOS气敏材料的设计提供了可靠的实验数据和思路。