基于低维导电高分子/II-VI族半导体异质结型柔性紫外光探测器的构筑及性能研究

The ultraviolet (UV) photodetector has a widely application in missile warning, medical/biological analysis and so on. Without the need of an external energy supply, the heterojunction devices with a built-in potential difference acting as a driving force exhibit high sensivity and high detectivity, which is an active demand of the UV detections. UV photodetectors based on low-dimensional Group II-VI semiconductors (ZnSe, ZnS, SnO2 and ZnO) have been attracted much attention. There still exists the problem of low photocurrent, sensivity and response speed, and the lack of efficient and stabilization p-type doping. Herein, the proposed project aims to the tunable synthesis low-dimensional Group II-VI semiconductors nanostructures, and then based on for subsequent research, the combined with one-dimensional conducting polymers nanofibers by electrospinning. A novel type of flexible heterojunction photodetector devices based on n-type low-dimensional Group II-VI semiconductors with various morphologies and p-type conducting polymers (doped-polyaniline, polyprrole and polythiophene) is developed. By optimizing the electrical conductivity of conducting polymers, the performance of UV devices can be accordingly improved. The proposal will conduct systematically study on the growth mechanism of low-dimensional Group II-VI semiconductors nanostructures and the variation of the conductivity of conducting polymers at different doping levels to get more insight into the inherent relationships between the performances of the UV devices and structures, physical properties. The research work will be to develop an efficient and reliable way to construct the high performances UV photodetectors based on organic/inorganic nanocomposites, which might provide a new approach to realize hybrid inorganic/organic flexible devices in the theory and practice.

随着紫外探测技术在导弹预警、医疗/生物监测等领域的广泛应用，迫切需要具有较高灵敏度和探测率以及不施加偏压时能稳定地工作的自驱动式紫外光探测器。目前，低维II-VI族半导体光探测器存在较低光电流、灵敏度和响应速度以及pn结构筑中p型较少的问题。针对以上难题，本项目拟在可控生长II-VI族低维半导体（ZnSe、ZnS、SnO2、ZnO）纳米结构的基础上，采用界面自组装法以静电纺丝的导电高分子纳米纤维作柔性衬底复合II-VI族低维半导体构筑II型有机/无机异质结能带结构，避开p型掺杂的难题，通过调控质子酸掺杂导电高分子纳米纤维的电导率优化光电性能。深入研究低维导电高分子和II-VI族半导体的生长机制，揭示紫外光探测器性能和复合纳米结构形貌、微结构等之间的相互关系和内在物理机制；发展一种简单适用的构筑低维有机/无机异质结方法，为柔性低维纳米器件的研发提供完善的实验基础和理论依据。

设计一种具备高灵敏度和探测率以及不施加偏压时能稳定地工作的自驱动式光电探测器，是现代社会发展的迫切需求。目前，低维II-VI族半导体光探测器存在较低光电流、灵敏度和响应速度以及pn结构筑中p型较少的问题。本项目首先采用原位聚合的方法制备了一种基于p型硒纳米花和p型聚苯胺的新型异质结结构，实现了自驱动的光电性能。采用静电纺丝技术制备了一维二氧化钛纳米纤维，利用p型硒纳米颗粒修饰构筑异质结，扩展了二氧化钛的检测范围，提高了器件的响应度和响应速度。其次聚苯胺作为超级电容器的电极材料，研究其电化学性能，最后通过模拟仿真光电探测器的工作机理，以及集成自旋磁随机存储器的制备工艺、校准技术，极大的提高了新型半导体集成器件的可能性。本项目的开展对研制新型有机/无机异质结的光电器件提供了一定的理论依据和实验成果，推动了光电器件材料研究的进一步发展。