通过对强相互作用的 Re ((0001) 和它们的电子性质进行修补的 h-BN 边界产生的不可弥补的缺陷
Yue Qi1, Zhepeng Zhang1, Bing Deng1
1Center for Nanochemistry (CNC), Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, People's Republic of China.
Journal of the American Chemical Society
|April 11, 2017
概括
六角化物 (h-BN) 的缺陷源于域补丁,改变电子特性. 了解这些缺陷可以通过缺陷工程调整材料特性.
科学领域:
- 材料科学
- 凝聚物质物理学
- 表面科学
背景情况:
- 缺陷极大地影响材料的性能,包括机械,电子和磁性特性.
- 控制缺陷对于定制材料性能至关重要.
- 六角化物 (h-BN) 是一种具有可调节电子特性的关键二维材料.
研究的目的:
- 在Re000001上增长h-BN单层时形成的缺陷类型.
- 通过这些缺陷调节的电子属性.
- 阐明系统中缺陷形成的机制.
主要方法:
- 在Re(0001) 表面上对h-BN生长的实验观测.
- 域修补边界的分类 (BadosaN,BadosaB,NadosaN).
- 由此产生的缺陷的特征 (moiré,线路缺陷) 和它们的电子影响.
主要成果:
- 三种类型的域修补边界导致不同的缺陷:"心脏"moiré,非绑定线和绑定线缺陷.
- 这些缺陷显著降低了h-BN的带间隙 (从约3.7 eV) 并引入间隙状态.
- 二元组合的h-BN和强大的基质相互作用促进缺陷的形成.
结论:
- 这项研究将2D材料领域补丁产生的缺陷分类.
- 缺陷工程提供了一个调节h-BN电子属性的途径.
- 了解缺陷的起源是先进材料设计的关键.
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