基于氧化石墨烯的B-C-N-O能带调控及其光电特性研究

Graphene has caused great interests in the scientific community because of the unique quantum effect. As a kind of zero band gap semiconductor, the two-dimensional single atomic layer has a high electrical conductivity, which otherwise limits its applications in the microwave absorbing field. However, the band gap of graphene can be easily tuned by doping boron and/or nitrogen, and then the optical and electrical properties are also expected to be tunable. Expected to develop a new type of nano-absorbent and light-emitting materials. It is finally apply to the camouflage and protection of the Equipment.The project intends to depart from the graphene oxide through B、N elements of the single / co-doping preparation B-C-N (or B-C-N-O),through the method of covalent binding for controlled modification of graphene, we plan to investigate the mechanism of regulation of reaction process and structure, electron transfer principle between graphene and doping atoms and doped graphene component performance. We will then assemble a number of two-dimensional film structure with functionalized graphene as the basic unit.Through studying the impact of material preparation on resulting BCNO film structure, morphology, defect, chemical composition and distribution we hope to clarify the mechanism of its assembly. Additionally, we will systematically research the new functionality of the materials due to the assembly structure and investigate the effect of material type and content of the film's flaws BCNO doping on carrier concentration, dipole, and other characteristics of the band gap. Finally, we will explore its high temperature absorbing properties and photoluminescence properties.

石墨烯因其奇特的量子效应成为当今科学界的研究热点。作为二维单原子层，石墨烯属于零带隙半导体，导电性极好，对电磁波呈反射特性，因此吸收电磁波的能力受到限制。然而，硼、氮掺杂石墨烯，即石墨烯与氮化硼有机结合，能够生成带隙可调的B-C-N-O材料，具有可调的光、电特性，有望开发出新型的纳米吸收剂与发光材料，最终应用于装备的伪装与防护。本项目拟由B、N单/共掺杂氧化石墨烯出发，通过共价键结合对石墨烯进行可控修饰，分析掺杂原子与石墨烯之间的电子传输机理，研究掺杂组分对石墨烯性能的影响，并以功能化石墨烯为基本单元组装出具有多层次有序结构的二维薄膜结构。研究制备工艺对所得B-C-N-O薄膜结构、形貌、缺陷、化学组成及其分布的影响，阐明其组装机理，系统研究组装结构赋予材料的新功能，探索掺杂物质种类与含量对B-C-N-O薄膜的缺陷、载流子浓度、偶极子、带隙等特征的影响，研究其高温吸波性能与光致发光特性。

石墨烯，二维单层碳原子材料，是构成碳材料家族的最基本单元。其轻质、层薄，理论厚度只有0.35 nm。表面无含氧基团，呈化学反应惰性。石墨烯是零带隙材料，可利用硼、氮掺杂打开石墨烯带隙结构，生成带隙可调的B-C-N-O光电材料。.本项目在前期研究的基础上，做了以下几部分工作：.1.利用氧化石墨烯与硼酸、尿素在空气气氛中进行高温反应，制备了紫外光致发红光的BCNO材料；.2.利用简易微波反应法，制备紫外光致发蓝光的BCNO材料。通过对比碳量子点和葡萄糖与硼酸、尿素反应产物结构与性能，分析所得材料发光机理，并将所制备BCNO发光粉末制备成LED灯珠。.3.利用氧化石墨烯与氨硼烷反应，制备层间掺杂的h-BN/石墨烯复合材料，并通过调控氧化石墨烯与氮化硼反应比例，制备针对不同电磁波段损耗的吸波材料，并探索其吸波机理；.4.利用搅拌剥离法和氧化剥离法制备单层（或少层）h-BN分散液，通过对比发现，搅拌剥离法剥离h-BN效果明显优于氧化剥离法；.5.利用微波反应法一步制备掺杂h-BN的蜂窝状石墨烯复合材料，并通过调控石墨烯和h-BN反应比例，调节复合材料带隙，从而实现对不同频段电磁波的损耗。