碳化硅纳米颗粒表面石墨烯量子点生长机制与形貌调控的理论研究

项目名称： 碳化硅纳米颗粒表面石墨烯量子点生长机制与形貌调控的理论研究

项目编号： No.11204260

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理学I

项目作者： 唐超

作者单位： 湘潭大学

项目金额： 25万元

中文摘要： 近年来，石墨烯研究备受人们的关注。石墨烯因其具有许多优异的物性，在光、电、磁、力学、生物等领域都有潜在的应用。随着石墨烯尺寸的减小，它表现出独特的量子约束及边界效应，引发了一些新的物理性质。不过，纳米级的石墨烯片难以制备，这限制了它应用于"量子点"这一半导体组件的前景。虽然经过精细加工可以将石墨烯片切割成各种形状的量子点，但石墨烯量子点的大规模直接生长一直是材料学研究的难题之一。本项目将利用第一性原理计算与分子动力学模拟方法系统研究碳化硅纳米颗粒表面石墨烯生长的动力学过程，分析碳化硅颗粒表面原子的扩散、解附等行为与石墨烯的成核、生长，以及形貌演变之间的内在关联，建立纳米颗粒表面石墨烯生长的微观物理模型，揭示其生长机制；并通过模拟获取纳米颗粒表面石墨烯的最佳生长条件、生长取向，精确调控石墨烯生长尺寸、形状及厚度，探索碳化硅纳米颗粒表面直接外延生长石墨烯量子点的方法。

中文关键词： 石墨烯；生长机制；形貌调控；第一性原理计算；分子动力学模拟

英文摘要： The research of graphene is always given to attention in recent years. Because of its unique physical properties, graphene have great potential applications in many fields, such as optics, electricity, magnetics, mechanics and biology. With decreasing its size, graphene exhibits unique quantum confinement and edge effects, given rise to some new physical properties. However, it is difficult to prepare the nanoscale graphene sheets, which limits its applications in area of semiconductor quantum dot materials. Although graphene quantum dots (GQD) can be obtained by cutting graphene sheets, direct growth of GQD is a difficult question in material science. In this project, a kinetic growth process of grpahene on surface of Silicon Carbide (SiC) nanoparticles is investigated using the molecular dynamics simulations and the first principle calculation. The intrinsic relation among the five kinds of dynamical behaviors, which are adatom diffusing, adatom desorption, nucleation of graphene, growth of graphene and microstructure evolution of graphene, is analyzed. A kinetic growth model of graphene on surface of SiC nanoparticles will be established, which can reveal the growth mechanism of graphene. Our research focus on obtaining the optimum growth conditions and preferred orientation of graphene on surface of SiC nano

英文关键词： graphene；growth mechanism；morphological controlling；first principle calculation；molecular dynamics simulation