基于结构性有机半导体薄膜的高性能气体传感器制备和机理探索

Gas sensor that could detect a certain gas species in different environment is one of the critical elements in many fields such as environment monitor, food detection, health care, security and industry process control. Common commercial product that use metal oxide exist obvious drawback such as low selectivity, limited sensitivity and high operating temperature. Organic semiconductors, as one of the most promising candidates for gas sensing, have attracted extensive attentions because of their expectations of achieving good selectivity, portability and low cost. Highly ordered structured organic semiconductor thin films is one promising access for high performance gas sensors owing to the good charge transport ability and large surface to volume ratio. Here we propose to develop a series of high performance gas sensos based on selected a series high mobility organic semiconductors and formed into finely assembled structured organic semiconductors films that hope to combine the advantages good charge transport and well defined film texture of organic materials. This structured organic semiconductor films could provide a fast response and recovery path for target gases, and the ordered films of high mobility materials could maintain the electric property and high sensitivity performance. The organic semiconductors are controllable aggregated on the patterned templates to achieve structured films that could afford high selectivity and sensitivity. We will conduct studies from assembling, characterization and gas sensor optimization of the system, aim to obtain high performance gas sensor combined with fully understanding of the sensor mechanism of organic semiconductor gas sensors.

气体传感器在环境监测、食品检测、健康检测和工业监控等领域充当着关键的一员。然而，目前市场主体的半导体传感器存在着工作温度高、选择性差和低灵敏度的问题。有机半导体由于化学结构可调、可大面积制备以及兼容柔性制备技术，在高选择性低成本气体传感器上具有潜在的应用价值。然而，有机半导体本身的弱相互作用、低输运能力等限制了其灵敏度和响应回复时间等性能。高有序、取向组装的有机半导体薄膜由于较高的电荷传输、大面积的气体作用通道，是实现高性能传感器的一个可能出口。本项目拟选取系列高迁移率有机半导体材料，结合表面图案化技术和修饰技术来实现高有序的结构性有机半导体薄膜的取向可控制备。有序的堆积组装在保证电学性质下可以发挥出有机半导体的选择性、高灵敏性，并可调节表面积和厚度以提高响应和回复时间，有效提高传感特性。本项目将从结构化薄膜的可控组装到传感器优化和机理进行系统研究。

气体传感器在环境监测、食品检测、健康检测和工业监控等领域充当着关键的一员。然而，目前市场主体的半导体传感器存在着工作温度高、选择性差和低灵敏度的问题。有机半导体由于化学结构可调、可大面积制备以及兼容柔性制备技术，在高选择性低成本气体传感器上具有潜在的应用价值。然而，有机半导体本身的弱相互作用、低输运能力等限制了其灵敏度和响应回复时间等性能。高有序、取向组装的有机半导体薄膜由于较高的电荷传输、大面积的气体作用通道，是实现高性能传感器的一个可能出口。结合器件物理和分子结构调控，是实现高性能气体传感的一种重要策略。本项目选取系列高迁移率有机小分子和聚合物材料，结合表面修饰和表面图案化技术实现高有序的结构性有机半导体薄膜的制备以及阵列晶体的选区生长。与此同时结合表面修饰基团化学性质差异，利用界面电荷转移从形态和电子性质两方面来调控气体传感器性能，实现了高灵敏NO2, NH3气体传感器的制备，并系统总结出构筑高性能气体传感器的规律和传感机制。基于系列高质量TIPS-pentacene薄膜的气体传感器对NO2灵敏度达到2000%/ppm,同时可以实现快速响应回复，在空气和湿度氛围下均表现较好的稳定性，是有可能进一步实现面向商业化的高性能气体传感器。此外，本项目开发的系列薄膜在光探测上也展现出较高性能，为进一步开发其他类传感器提供基础。