基于ZnO/石墨烯纳米结构的新型柔性紫外探测器的设计和机理研究

Flexible and wearable photodetectors especially ultraviolet photodetector have become the mainstream research trend in the optoelectronic field in recent years. As traditional inorganic wide bandgap semiconductors are usually brittle and fragile due to their unique features of lattices structures, how to achieve a novel UV photodetector based on inorganic semiconductor with flexibility in the material itself still remains a big challenge. Making the most use of the relative mobile among each single nanostructure is effective method to reduce the deformation influence on the performance of detectors. Herein, we aim to fabricate high-quality flexible ZnO nanofilms via a self-assembled method through optimizing the morphology, size and way of integration. And novel UV photodetectors will be constructed by combining the as-obtained ZnO film and metal nanonetworks. Meanwhile, considering the defects of intrinsic ZnO materials, graphene nanomaterials will be used to modify the surface of ZnO nanostructures, which can further improve the photoelectric properties of detectors. Finally, systematical investigation of their physical mechanism will be studied carefully. This project would provide important experiment results and theoretical basis for the application of inorganic semiconductors in novel flexible UV photodetectors, and offer guidance on the development of related flexible electronic devices.

柔性、可穿戴的光探测器，尤其是紫外探测器，近年来逐渐成为光电子领域的研究主流。由于其晶格结构的特点，传统无机宽禁带半导体材料往往面临着较脆、易碎的问题，如何制备出基于无机半导体材料的柔性紫外光探测器面临着巨大的挑战。利用纳米结构之间的相对运动来降低外界形变对器件结构和性能产生的影响，是制备柔性探测器的有效方法。本项目拟以ZnO纳米材料为主体，采用自组装的方法，通过调控ZnO纳米结构的形貌、尺寸及组装方式，制备出具有较高柔性的ZnO薄膜。然后以金属纳米网格作为柔性透明电极，构筑出新型的柔性紫外探测器。同时，考虑到ZnO纳米材料本身的缺陷，我们拟用石墨烯纳米结构对其进行修饰来进一步提高器件整体的探测性能。最终对整体器件的内在物理机理进行详细研究分析。本项研究将为传统无机半导体材料在新型柔性紫外探测器中的应用提供重要的实验基础和理论依据，并为相关柔性电子器件的研发提供新的思路。

借助于纳米材料结构尺寸较小，相互之间可以相对移动的特点，通过自组装的方法让纳米颗粒形成较为致密的薄膜，是实现基于无机宽禁带半导体材料柔性器件的有效方法。本项目研究了ZnO纳米结构的形貌和柔性衬底对ZnO基柔性紫外探测器的影响，及提高ZnO基紫外探测器响应速度的有效方法。实验结果表明，1）在常见的柔性衬底中，相对于PET跟A4纸，在滤纸上所制得探测器的柔性及稳定性较好；2）相对于无规则的纳米颗粒，纳米球状结构在制备柔性探测器时具有较为明显的优势；3）高长径比的纳米线也能够制备出柔性较好的探测器；4）而构建异质结结构是提高ZnO基探测器响应速度的有效方法；5）在ZnO纳米颗粒间引入石墨烯纳米片，能够有效提升器件的光电流和响应度。所得这些实验结论为后续ZnO基柔性紫外光电探测器的进一步研究与发展提供数据基础。在本项目的支持下，共发表学术论文7篇，申获国家实用新型发明专利1项，培养硕士研究生5名，参与科研训练本科生8名。整体来看，项目的成果产出及人才培养情况都较为圆满的完成了预定的研究任务。