Epitaxial Growth of h‐BN on Templates of Various Dimensionalities in h‐BN–Graphene Material Systems

Abstract

2D in-plane and vertical heterostructures such as graphene and hexagonal boron nitride (h-BN) have drawn wide attention owing to their unique structure and properties over the past years. [1][2][3][4][5][6] Previous studies have explored their controlled growth, detailed interface microstructure, properties, and device applications. [7] For example, the interface of in-plane or vertical heterostructures can be controlled to be atomically sharp or clean at a proper growth condition, and the intriguing properties such as half-metallicity, [8] magnetism, [9] or peculiar boundary states [3,10] have been theoretically predicted or partly confirmed by experiments. On the other hand, the in-plane heterostructure system is also an ideal system for deeply studying related epitaxy behavior and kinetic process beyond conventional A-A or A-B material systems. For example, grapheneh-BN system provides a rich possibility of epitaxial templates with various dimensionalities and interface, such as 2D crystal surfaces, 1D edges, inner 1D grain boundaries (GBs), and 1D interface of graphene-h-BN. Among these possibilities, 1D graphene zigzag (ZZ) edges were previously studied in depth for the epitaxial growth of h-BN. [11,12] While h-BN growth along other various graphene edges fabricated by top-down etching was also demonstrated, graphene edge configurations are essentially unknown. [13,14] However, much less is known about the related kinetic growth of complex epitaxial systems. To date, it is not clear whether the growth of 2D materials on templates of various dimensionalities is allowed in practice, and no effective idea or model is available for describing the complex epitaxial growth kinetics.Here, using a 2D A-B (A: graphene and B: h-BN) system with the freedom of in-and out-of-plane epitaxial growth, we discover a set of new epitaxial growth patterns, spanning from edge-configuration-dependent growth along 1D graphene ZZ to armchair (AC) edges, GB formation by merging materials, 1D GB-or A-B interface-templated growth of adlayer, to adlayer growth on 2D surface template. We further provide, for the first time, a framework that allows the description of various kinetic growths of epitaxial structures by combined geometric and structural modeling. This work provides a general viewpoint for understanding epitaxial growth in complex systems.We started the growth of single crystal hexagonal graphene flakes (HGFs) with desired sizes and densities on liquid Cu surface by modulating experimental parameters such as methane, H 2 , and Ar flow rates. [15] The formed regular monolayer HGFs Epitaxy traditionally refers to the growth of a crystalline adlayer on a crystalline surface, and has been demonstrated in several simple material systems over decades. Beyond this, it is not clear whether the growth of 2D materials on templates of various dimensionalities is possible, and no effective theory or model is available for describing the complex epitaxial growth kinetics. Here a library of hexagonal boron nitride epitaxy is presented on ...

Advances in the Applications of Graphene-Based Nanocomposites in Clean Energy Materials

“…The surface passivation, functionalization, heteroatom doping or recombination of graphene quantum dots meets the needs of different applications. In the SiC epitaxy growth method, SiC single crystal is heated at a high temperature so that the Si atoms on the surface of SiC are evaporated and separated from the surface and the remaining carbon atoms are reconstructed by self-assembly to obtain graphene based on silicon carbide substrate [38].…”

Controllable synthesis of graphene by CVD method

“…随后, 在无机衬底上外延, Cu(111) [96] 、Ni . 对H 2 刻蚀石墨烯的进一步研究表明, H 2 会 对石墨烯产生各向异性的六重对称效果 [101] , 通过调整 [103] 还研究了石墨烯/h-BN异质 图 3 (网络版彩色)石墨烯形状调控及石墨烯/h-BN异质结构形成过程. (a)~(c) 不同氩气/氢气比例下液态铜上高度规则的六方对称的石墨烯典 型SEM图像, 所有标尺为5 μm [92] ; (d) 基于石墨烯的各向异性生长, 模拟了多边形石墨烯薄片中石墨烯晶界的形成机理, 图中显示的是3个石墨 烯核同时合并; (e) 多边形石墨烯薄片上的SEM图像, 显示晶界上的位置对应于多边形的某个顶点, 其中相关角度不等于120°, 标尺为100 μm [94] ;…”

Research progress of IV–VI low-dimensional semiconductor materials and devices

“…发现通过机械剥离的方法制备得到了单层石墨烯薄膜，并且该薄 膜具有超大的比表面积、良好的面内电导率、超高的载流子迁移率等特性，这些性质可以应用 在高频光电探测器中 [2] ，因此该研究引起了学术界对层状材料的广泛关注 .与无带隙宽度的石墨 烯不同，具有一定带隙结构的不同体系的二维层状材料逐渐引起研究者的广泛关注 [3] .典型的二 维层状材料包括过渡金属硫化物(TMDCs) [4][5][6] 、 过渡金属碳化物/氮化物(MXenes) [7,8] 、黑 磷(BP) [9][10][11] 、六方氮化硼(h-BN) [12,13] 、 层状金属二卤化物(LMDCs) [14] 等.其中，过渡金属硫化 物克服了石墨烯零带隙的限制，所制备的场效应晶体管具有较大的开关比 [15] ；并且对于部分具 有特殊晶体结构的过渡金属硫化物，在电子器件、光电子器件等领域中有重要应用. [16,17] 二维材 料层内以较强的共价键结合, 层间以较弱的范德瓦尔斯(范德华)力结合 [18] ,所以容易剥离,且表面 没有悬挂键，可以容易的实现材料转移.通常单层二维半导体材料的能带结构主要为直接带隙结 构，因此可以产生优异的光学性质.并且，在光电器件应用中 [19][20][21][22][23][24][25][26][27][28][29][30][31] ，二维材料纳米量级的厚度可 以有效的减少由载流子产生-复合而产生的噪声 [32] .因此，二维材料在未来新型光电器件领域具 有很大的应用前景.…”