Iakovlev Evgeny, Zhilyaev Petr, Akhatov Iskander
Center for Design, Manufacturing and Materials, Skolkovo Institute of Science and Technology, Moscow, Russia.
Sci Rep. 2017 Dec 20;7(1):17906. doi: 10.1038/s41598-017-18226-9.
A two-dimensional (2D) material placed on an atomically flat substrate can lead to the formation of surface nanobubbles trapping different types of substances. In this paper graphene nanobubbles of the radius of 7-34 nm with argon atoms inside are studied using molecular dynamics (MD). All modeled graphene nanobubbles except for the smallest ones exhibit an universal shape, i.e., a constant ratio of a bubble height to its footprint radius, which is in an agreement with experimental studies and their interpretation using the elastic theory of membranes. MD simulations reveal that argon does exist in a solid close-packed phase, although the internal pressure in the nanobubble is not sufficiently high for the ordinary crystallization that would occur in a bulk system. The smallest graphene bubbles with a radius of 7 nm exhibit an unusual "pancake" shape. Previously, nanobubbles with a similar pancake shape were experimentally observed in completely different systems at the interface between water and a hydrophobic surface.
放置在原子级平整衬底上的二维（2D）材料可导致形成捕获不同类型物质的表面纳米气泡。本文使用分子动力学（MD）研究了内部含有氩原子、半径为7 - 34纳米的石墨烯纳米气泡。除最小的气泡外，所有模拟的石墨烯纳米气泡都呈现出一种通用形状，即气泡高度与其底面半径的恒定比例，这与实验研究以及使用膜弹性理论对其的解释一致。分子动力学模拟表明，尽管纳米气泡内的内部压力不足以使在体系统中发生的普通结晶过程发生，但氩确实以固体密堆积相存在。半径为7纳米的最小石墨烯气泡呈现出不寻常的“薄饼”形状。此前，在水与疏水表面之间的界面处，在完全不同的系统中通过实验观察到了具有类似薄饼形状的纳米气泡。
