Achehboune Mohamed, Zhour Kazem, Dabrowski Jaroslaw, Vignaud Dominique, Franck Max, Lukosius Mindaugas, Colomer Jean-François, Henrard Luc
Laboratoire de Physique du solide, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles 61, 5000, Namur, Belgium.
Institute of Physical Chemistry, University of Münster, Corrensstraße 28/30, Münster 48149, Germany.
Phys Chem Chem Phys. 2024 Nov 13;26(44):28198-28207. doi: 10.1039/d4cp03300k.
Graphene and hexagonal boron nitride (hBN) are two-dimensional (2D) materials with a similar atomic structure but drastically different although complementary electronic properties. The large-scale synthesis of h-BN/graphene heterostructures with high crystallographic quality is required to fully benefit of the graphene electronic properties. In this study, we examine numerically the interaction of graphene precursors on hBN and of hBN precursors on graphene to gain deep insight of the CVD and MBE growth mechanism of graphene/hBN heterostructures. Density functional theory (DFT) calculations reveal the adsorption and diffusion behaviors for B, N, and C atoms on these surfaces. In particular, the adsorption energy is found to be similar to the diffusion barriers, except for the nearly free diffusion of B atoms on both graphene and hBN. We have also investigated the transition from individual atoms to graphene or h-BN seeds by considering the stability of linear chains as well as branched and ring seeds. Furthermore, for larger clusters, the triangular h-BN domains are found to be equally thermodynamically stable on graphene regardless of their orientation. These findings provide preliminary hints for the ability of graphene to grow on hBN layers and hBN layer on graphene.
石墨烯和六方氮化硼（hBN）是具有相似原子结构的二维（2D）材料，但电子特性截然不同却又相互补充。为了充分利用石墨烯的电子特性，需要大规模合成具有高晶体质量的h-BN/石墨烯异质结构。在本研究中，我们通过数值方法研究了石墨烯前驱体在hBN上以及hBN前驱体在石墨烯上的相互作用，以深入了解石墨烯/hBN异质结构的化学气相沉积（CVD）和分子束外延（MBE）生长机制。密度泛函理论（DFT）计算揭示了B、N和C原子在这些表面上的吸附和扩散行为。特别是，除了B原子在石墨烯和hBN上几乎自由扩散外，发现吸附能与扩散势垒相似。我们还通过考虑线性链以及分支和环状晶种的稳定性，研究了从单个原子到石墨烯或h-BN晶种的转变。此外，对于较大的团簇，发现三角形h-BN畴在石墨烯上无论其取向如何都具有相同的热力学稳定性。这些发现为石墨烯在hBN层上生长以及hBN层在石墨烯上生长的能力提供了初步线索。
