Universal shape of graphene nanobubbles on metallic substrate
Universal shape of graphene nanobubbles on metallic substrate
复制标题
金属基底上石墨烯纳米气泡的通用形状
DOI：
10.1039/d1cp05902e
复制
发表时间：
2022
影响因子：
3.3
通讯作者：
Aslyamov T
中科院分区：
文献类型：
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作者：
Aslyamov T
石墨烯纳米气泡（GNB）是由二维材料和基底之间捕获的物质形成的。这样的结构表现出广泛的新的基本现象，并有望为纳米电子应用。然而，合成方法的核心部分导致形成具有不确定物质组成的GNBs。此外，GNB的合成方法都不允许控制捕获物质的类型。在最近的一篇论文[K。M. Zahra，PCCP，22，7606（2020）]，作者提出了一种新的方法，该方法允许以受控的方式在内部具有纯氮的铜衬底上生产GNB。在这项工作中，我们通过详细研究GNBs的几何形状并间接测量内部压力来继续这项研究，该内部压力取决于石墨烯膜的货车德瓦尔斯粘附能和弹性特性。与其他研究一致，我们观察到圆顶形气泡表现出普遍的标度律，即，恒定的高径比。然而，测量的高度与半径比与已知的实验和计算机模拟结果有很大不同。通过应用膜理论并考虑铜衬底和石墨烯片的高粘附性来解释这种偏差。基于实验数据计算的粘附能与其他实验技术测量的粘附能接近。
Graphene nanobubbles (GNBs) are formed from matter trapped between a two-dimensional material and a substrate. Such structures exhibit a wide range of new fundamental phenomena and are promising for nanoelectronic applications. However, a central part of the synthesis methods leads to the formation of GNBs with undetermined matter composition. Moreover, none of the GNBs’ synthesis methods allow one to control the type of trapped matter. In a recent paper [K. M. Zahra, PCCP, 22,7606 (2020)], the authors proposed a new approach that allows the production of GNBs on a copper substrate with pure nitrogen inside in a controlled manner. In this work, we continue this research by studying the geometry of the GNBs in detail and indirectly measuring the internal pressure, which depends on the van der Waals adhesion energy and elastic properties of the graphene membrane. In agreement with other studies, we observe that dome-shaped bubbles exhibit universal scaling law, i.e., constant height to radius ratio. However, the measured height to radius ratio differs significantly from the known results of experiments and computer simulations. This deviation is explained by applying the membrane theory and taking into account the high adhesion of the copper substrate and graphene sheet. The adhesion energy calculated based on experimental data is close to the measurements performed by other experimental techniques.