Density functional study of Ga intercalation at graphene/SiC heterointerface
Density functional study of Ga intercalation at graphene/SiC heterointerface
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石墨烯/SiC异质界面Ga嵌入的密度泛函研究
DOI：
10.1557/s43578-022-00530-4
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发表时间：
2022-03
影响因子：
2.7
通讯作者：
Nadire Nayir
中科院分区：
文献类型：
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作者：
Nadire Nayir
插层技术在二维材料领域引起了极大的关注，能够在石墨烯/碳化硅的异质界面上制造原子级薄且稳定的非层状材料，例如Ga。然而，这种界面处金属嵌入的原子机制仍有待了解。在这项研究中，第一性原理计算提供了对 Ga 渗透到 SiC/石墨烯界面和在 SiC/石墨烯界面处成核的热力学和动力学水平的理解。封装在石墨烯/SiC界面上的Ga原子在热力学上比吸附在石墨烯层顶部上更稳定，这表明在2D Ga生长过程中需要利用SiC衬底来促进Ga迁移到SiC/石墨烯界面中。此外，Ga原子和空位缺陷的尺寸对于Ga渗透石墨烯至关重要，影响Ga原子在石墨烯上吸附或嵌入SiC/石墨烯通道之间的热力学和动力学偏好。
The intercalation technique has harnessed tremendous attention in the 2D materials’ community, enabling to fabricate atomically thin and stable non-layered materials such as Ga at the heterointerface of graphene/SiC. However, the atomistic mechanism of the metal intercalation at such interface has still yet to been understood. In this study, first-principles calculations provide a thermodynamic and kinetic level understanding of the Ga penetration into and nucleation at the SiC/graphene interface. A Ga atom encapsulated at the graphene/SiC interface is thermodynamically more stable than adsorbed on the top of the graphene layer, signifying the necessity of exploiting the SiC substrate during the 2D Ga growth to facilitate the Ga migration into the SiC/graphene interface. Additionally, the sizes of a Ga atom and vacancy defect are critical to the Ga penetration through graphene, affecting the thermodynamic and kinetic preference of a Ga atom between the adsorption on graphene or the intercalation in to the SiC/graphene gallery.