石墨烯柔性气体传感器关键材料、工艺与敏感特性研究

With the rapid development of flexible electronic technology and internet of things, flexible gas sensors show a broad application prospects in intelligent, portable and wearable devices. In our project, we present a module of new flexible gas sensor structure based on graphene-sensitive channel. The graphene will be used for its excellent characteristics in terms of high mobility, transparency, flexibility, low-cost and compatibility with flexible integrated circuits, ZnO hierarchical nanostructure will be combined with graphene to prepare functionalized graphene-sensitive film. We will establish and optimize the theoretical model of graphene nanocomposites based flexible gas sensor through the simulation and modeling of materials and devices, and thoroughly investigate the response of gas molecules in the dynamic process within graphene nanocomposite materials, and then study the change of carrier transport behaviors in the sensitive tunnel. The sensitive mechanism about graphene nanocomposites based flexible gas sensor will be further revealed. The composite method of graphene and ZnO hierarchical nanostructure as well as the film preparation processes on the flexible substrate will be studied and optimized. The key technology and growth processes compatible with CMOS technology will also be explored. Finally, the graphene based flexible gas sensor with high sensitivity and fast response will be fabricated, providing research methods and directions in the graphene based flexible gas sensor applications.

随着柔性电子技术及物联网技术的飞速发展，柔性气体传感器将在智能化、便携化及可穿戴设备中具有广泛的应用前景。本项目将利用石墨烯对气体分子独特的敏感特性、高迁移率、透明柔性及可实现柔性集成的特点，结合氧化锌多级纳米结构，构建石墨烯功能化敏感薄膜，提出并设计基于石墨烯敏感沟道的新型柔性气体传感器结构。通过材料与器件的模拟与仿真，建立并完善基于石墨烯纳米复合结构的柔性气体传感器理论模型，深入探讨气体分子在石墨烯纳米复合材料中的响应动力学过程及由此引起的载流子输运行为的变化规律，进一步揭示石墨烯纳米复合柔性气体传感器敏感机理与调控方法；研究并优化石墨烯与ZnO多级纳米结构的复合方法及其在柔性衬底上的成膜工艺；探索与CMOS工艺兼容的器件柔性化关键技术及其制备方法，最终获得具有高灵敏度和快速响应的石墨烯柔性气体传感器件，为石墨烯在柔性气体传感器中的应用提供一种可行的研究思路和实现途径。

为满足柔性电子技术及物联网技术等高新领域对高性能、可穿戴、柔性气体传感器的需求，本项目对基于石墨烯及其复合结构的柔性气体传感器进行研究，探索其在可穿戴柔性气体传感应用中的关键科学问题。本项目从功能化气敏薄膜材料的制备、气体传感器结构设计、气敏特性分析、敏感机理研究以及柔性化关键技术等方面进行系统性的研究工作。首先，通过对多种石墨烯材料制备方法的研究，最终选取适用于气敏特性研究的氧化还原石墨烯(rGO)作为敏感材料。其次，探讨了多种成膜技术，制备了不同特性的rGO敏感薄膜，并对其微观结构进行表征。在此基础上，设计制备了基于rGO及其复合结构的柔性气体传感器，并对其气敏性能（气体响应特性、选择性、检测浓度、重复性和稳定性等）进行了测试分析。通过分析实验数据，建立并完善了rGO基复合结构薄膜的气体敏感机理的模型。进而，对石墨烯基纳米复合材料的制备方法及气敏特性开展了一系列研究工作，实现了基于rGO基复合结构柔性气体传感器件。与此同时，创新性地提出利用紫外光辅助提高气敏选择性的研究方法，以提高rGO基复合结构气体传感器的性能指标。最终，提出一种易操作、低成本、可扩展的rGO基复合结构气敏导电纤维制备方案，为石墨烯柔性气体传感器在可穿戴检测领域提供了研究思路和解决方案。