大面积改性石墨烯的制备及其分子探测与光电转换性能研究

With the increasing energy shortage and environmental pollutions, the research on novel clean energy materials and pollutant-detecting materials becomes more and more important from both scientific and practical point of views. As a new type of two-dimensional carbon materials, chemically doped graphene has the potential to be used in above fields in virtue of their interesting chemical, mechanical, electrical and optical properties. However, few experimental progress has been made along this line due to the limitation of synthesizing large-area, high-quality doped graphene sheets. We proposed to carry out research in the following two topics based on the successful synthesis of large-area, high-quality doped graphene. On the one hand, we will characterize their properties in high-sensitivity organic molecular sensing area based on surface-enhanced Raman scattering (SERS) effect. On the other hand, we will construct "doped graphene/semiconductor" heterojunction solar cell devices with few-layered transition metal dichalcogenide films. The conversion mechanism will also be systematically investigated. This proposal will greatly facilitate the development of high-sensitivity organic pollutants detection and novel inorgainc photovoltaic materials.

随着能源短缺和环境污染问题的不断突出，开发新型清洁能源材料和污染物探测材料将具有十分迫切的科学意义和实用价值。化学掺杂石墨烯作为一种新型的二维碳材料，由于其具有良好的化学、力学、电学和光学性能，有望在这些领域得到应用，但受制于大面积高质量掺杂石墨烯合成的瓶颈问题，相关的实验研究还非常少。本项目将在掺杂石墨烯材料成功合成的基础上，一方面结合石墨烯表面增强拉曼散射技术开展高灵敏度有机分子探测研究；另一方面拟将掺杂石墨烯与其它新型的二维半导体材料（如过渡金属硫化物薄膜）材料构建新颖的异质结太阳能电池，并系统研究其光电转换机制。本研究的成功开展将为高灵敏度环境污染物监测和新型无机薄膜太阳能电池光电转换材料的开发提供科学依据与可行途径。

开发高性能清洁能源材料和污染物探测材料具有重要的科学意义和实用价值，具有二维结构的化学掺杂石墨烯和过渡金属二硫化物（TMDCs）有望在这些领域得到应用，但受制于大面积高质量样品合成的瓶颈问题，相关的实验研究还非常少。本项目自主设计并搭建了鼓泡辅助化学气相沉积（BA-CVD）装置，实现了大面积（厘米尺度）高质量异质原子（B、S、Si 等）掺杂石墨烯的可控合成；通过扫描隧道显微镜（STM）、拉曼光谱、X射线光电子能谱（XPS）并结合密度泛函理论（DFT）模拟计算，对掺杂构型进行了原子级可视化解析；通过优化制备工艺，实现了对掺杂量、面电阻等物理性能的调控；基于所合成的材料，发现了由掺杂诱发的增强拉曼散射效应，实现了对有机/无机分子的高灵敏检测并揭示了其增强机制；基于所得到的大面积高质量石墨烯样品，通过引入减反射层，得到了高性能的异质结光伏器件；将石墨烯研究中形成的缺陷调控理念拓展到了其它二维层状材料体系，设计得到了高性能析氢催化材料和声压探测器件，进一步推动了二维材料在清洁能源转换和超灵敏探测领域的应用，对相关研究具有重要的参考价值。