Electron beam-induced nanopores in Bernal-stacked hexagonal boron nitride
Electron beam-induced nanopores in Bernal-stacked hexagonal boron nitride
复制标题
电子束诱导的六方氮化硼纳米孔
DOI：
10.1063/5.0010891
复制
发表时间：
2020-07-13
影响因子：
4
通讯作者：
Cohen, Marvin L.
中科院分区：
文献类型：
--
作者：
Dogan, Mehmet;Gilbert, S. Matt;Cohen, Marvin L.
控制二维材料中纳米孔的大小和形状是DNA测序、筛分和人工原子量子发射等应用中的关键挑战。本文从实验和理论两方面研究了利用高能电子束在（非常规）Bernal-stacked AB-h-BN中形成的三角形空位。由于AB-h-BN的几何构型，不同层间的三角形孔隙呈排列状，其大小受电子辐照时间长短的控制。空位边缘的层间共价键不受青睐，这与更常见的AA '堆叠BN相反。在高分辨率透射电子显微镜下观察到双层ab -h- bn中的各种单层、同心和双层孔隙，并使用从头算模拟对其进行了表征。在AB-h-BN中，双层孔隙通常在不破坏双层特性的情况下形成和生长。AB-h-BN的纳米孔表现出广泛的电子性质，从半金属到非磁性和磁性半导体。因此，由于孔径的可控性，电子结构在这些系统中也是高度可控的，并且可以针对特定应用进行潜在的调整。
Controlling the size and shape of nanopores in two-dimensional materials is a key challenge in applications such as DNA sequencing, sieving, and quantum emission in artificial atoms. We here experimentally and theoretically investigate triangular vacancies in (unconventional) Bernal-stacked AB-h-BN formed using a high-energy electron beam. Due to the geometric configuration of AB-h-BN, triangular pores in different layers are aligned, and their sizes are controlled by the duration of the electron irradiation. Interlayer covalent bonding at the vacancy edge is not favored, as opposed to what occurs in the more common AA ' -stacked BN. A variety of monolayer, concentric, and bilayer pores in the bilayer AB-h-BN are observed in high-resolution transmission electron microscopy and characterized using ab initio simulations. Bilayer pores in AB-h-BN are commonly formed and grow without breaking the bilayer character. Nanopores in AB-h-BN exhibit a wide range of electronic properties, ranging from half-metallic to non-magnetic and magnetic semiconductors. Therefore, because of the controllability of the pore size, the electronic structure is also highly controllable in these systems and can potentially be tuned for particular applications.