Aslyamov T F, Iakovlev E S, Akhatov I Sh, Zhilyaev P A
Center for Design, Manufacturing and Materials, Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow 121205, Russia.
J Chem Phys. 2020 Feb 7;152(5):054705. doi: 10.1063/1.5138687.
A graphene nanobubble consists of a graphene sheet, an atomically flat substrate, and a substance enclosed between them. Unlike conventional confinement with rigid walls and a fixed volume, the graphene nanobubble has one stretchable wall, which is the graphene sheet, and its volume can be adjusted by changing the shape. In this study, we developed a model of a graphene nanobubble based on classical density functional theory and the elastic theory of membranes. The proposed model takes into account the inhomogeneity of the enclosed substance, the nonrigidity of the wall, and the alternating volume. As an example application, we utilize the developed model to investigate fluid argon inside graphene nanobubbles at room temperature. We observed a constant height-to-radius ratio over the whole range of radii considered, which is in agreement with the results from experiments and molecular dynamics simulations. The developed model provides a theoretical tool to study both the inner structure of the confined substance and the shape of the graphene nanobubble. The model can be easily extended to other types of nonrigid confinement.
石墨烯纳米气泡由石墨烯片、原子级平整的基底以及夹在它们之间的一种物质组成。与具有刚性壁和固定体积的传统受限体系不同，石墨烯纳米气泡有一个可拉伸的壁，即石墨烯片，其体积可通过改变形状来调节。在本研究中，我们基于经典密度泛函理论和膜的弹性理论建立了一个石墨烯纳米气泡模型。所提出的模型考虑了被包裹物质的不均匀性、壁的非刚性以及交替变化的体积。作为一个示例应用，我们利用所建立的模型研究室温下石墨烯纳米气泡内的液态氩。在所考虑的整个半径范围内，我们观察到高度与半径之比恒定，这与实验和分子动力学模拟的结果一致。所建立的模型为研究被包裹物质的内部结构以及石墨烯纳米气泡的形状提供了一种理论工具。该模型可以很容易地扩展到其他类型的非刚性受限体系。
