Ma Chengfu, Chen Yuhang, Chu Jiaru
Langmuir. 2023 Jan 17;39(2):701-708. doi: 10.1021/acs.langmuir.2c02837. Epub 2023 Jan 3.
Understanding the mechanics of blisters is important for studying two-dimensional (2D) materials, where nanoscale blisters appear frequently in their heterostructures. It also benefits the understanding of a novel partial wetting phenomenon known as elastic wetting, where droplets are confined by thin films. In this two-part work, we study the static mechanics of nanoscale blisters confined between a 2D elastic sheet and its substrate (part 1) as well as their pinning/depinning dynamics (part 2). Here, in part 1, we investigate the morphology characteristics and hydrostatic pressures of the blisters by using atomic force microscopy (AFM) measurements and theoretical analysis. The morphology characteristics of the blisters are shown to be the interplay results of the elasticity of the capping sheet, the adhesion between the capping sheet and the substrate, and the interfacial tensions. A universal scaling law is observed for the blisters in the experiments. Our analyses show that the hydrostatic pressures inside the blisters can be estimated from their morphology characteristics. The reliability of such an estimation is verified by AFM indentation measurements of the hydrostatic pressures of a variety of blisters.
了解水泡的力学原理对于研究二维（2D）材料非常重要，在二维材料的异质结构中经常会出现纳米级水泡。这也有助于理解一种称为弹性润湿的新型部分润湿现象，即液滴被薄膜限制。在这项分为两部分的工作中，我们研究了限制在二维弹性片及其基底之间的纳米级水泡的静态力学（第一部分）以及它们的钉扎/去钉扎动力学（第二部分）。在这里，在第一部分中，我们通过使用原子力显微镜（AFM）测量和理论分析来研究水泡的形态特征和静水压力。水泡的形态特征显示为覆盖片的弹性、覆盖片与基底之间的粘附力以及界面张力之间相互作用的结果。在实验中观察到水泡的通用标度律。我们的分析表明，水泡内部的静水压力可以从其形态特征中估计出来。通过对各种水泡的静水压力进行AFM压痕测量，验证了这种估计的可靠性。
