六方BN薄膜生长机理的理论研究

项目名称： 六方BN薄膜生长机理的理论研究

项目编号： No.21303041

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 赵瑞奇

作者单位： 河南理工大学

项目金额： 25万元

中文摘要： 六方BN薄膜在可控调节石墨烯的带隙并保持其高的载流子迁移率方面具有巨大的应用前景，这使BN在短时间内成为物理、化学和材料领域的研究热点。但可控制备高质量大面积的h-BN是个难点，对其生长机理的研究更是远远落后于对石墨烯生长的理解。本项目聚焦于h-BN生长机理的研究，从理论的角度研究h-BN生长的影响因素和规律。研究内容包括：1. 利用第一性原理研究基底的种类和堆积方式在生长初期对BN排列方向的影响； 2.结合第一性原理和晶体生长理论，研究BN生长过程中原子的生长顺序和体系能量的变化，研究在接近平衡条件和远离平衡条件下影响BN生长的因素；3. 利用第一性原理研究BN的成核过程，重点研究基底对BN的成核尺寸、形状及边缘类型的影响。该项目的开展有助于理解BN生长过程中的影响因素，为可控制备高质量的BN和理解生长过程中观察到的各种现象提供理论参考和指导，也将为促进BN和石墨烯的应用起到促进作用。

中文关键词： 六方 BN；生长机理；密度泛函理论；过渡金属；化学气相沉积

英文摘要： Hexagonal BN (h-BN) films have huge implications in controllably tuning the gap size of graphene while keeping its high mobilities, which makes BN a hotspot in physics, chemistry, and materials. However, there is plenty of difficulty in the controllable synthesis of BN with high quality, and large area. And the understanding in the growth mechanism of h-BN falls far behind that of graphene. Here, we focus on the growth mechanism of h-BN and will study the factors and rules governing the growth of h-BN. It includes: 1. Study the influences of substrate type and stacking on the alignment of BN domains in the initial nucleation by density functional theory(DFT); 2. Study the sequence of adding B/N atoms to SP2 crystals, the corresponding variations in energy, and the factors influencing the shapes of BN prepared near and/or far away from equilibrium by DFT and crystal growth mechanism; 3. Study the nucleation process of h-BN, especially the substrate influence on the size, shape, and edge types. These work will be helpful in understanding the factors influncing the growth process of h-BN, what's more important, it will provide guidance in preparing BN with high quality and understanding the phenomena observed in experiments. It will also facilitate the applications of BN and graphene as electronic devices.

英文关键词： hexagonal BN；Growth mechanism；Density functional theory；Transition metals；Chemical vapor deposition