Klauser Waldemar, von Kleist-Retzow Fabian T, Fatikow Sergej
Division Microrobotics and Control Engineering, Department of Computing Science, University of Oldenburg, D-26129 Oldenburg, Germany.
Nanomaterials (Basel). 2022 Jan 24;12(3):369. doi: 10.3390/nano12030369.
Despite considerable research efforts, the influence of contact line tension during wetting at the nanoscale and its experimental determination remain challenging tasks. So far, molecular dynamics simulations and atomic force microscope measurements have contributed to the understanding of these phenomena. However, a direct measurement of the size dependence of the contact angle and the magnitude of the apparent line tension has not been realized so far. Here, we show that the contact angle is indeed dependent on the drop size for small drop diameters and determine the magnitude of the apparent line tension via liquid-metal based measurements of advancing and receding contact angle inside a scanning electron microscope. For this purpose, a robotic setup inside an electron microscope chamber and oxide-free Galinstan droplets-produced via an electromigration-based and focused ion beam irradiation-assisted process-are employed. Using the first-order correction of Young's equation, we find an apparent line tension value of 4.02 × 10 J/m for Galinstan© on stainless steel.
尽管进行了大量的研究工作，但纳米尺度下润湿性过程中接触线张力的影响及其实验测定仍然是具有挑战性的任务。到目前为止，分子动力学模拟和原子力显微镜测量有助于对这些现象的理解。然而，到目前为止尚未实现对接触角的尺寸依赖性和表观线张力大小的直接测量。在此，我们表明对于小液滴直径，接触角确实取决于液滴大小，并通过扫描电子显微镜内基于液态金属的前进和后退接触角测量来确定表观线张力的大小。为此，采用了电子显微镜腔内的机器人装置以及通过基于电迁移和聚焦离子束辐照辅助工艺产生的无氧化物镓铟锡液滴。使用杨氏方程的一阶校正，我们发现不锈钢上镓铟锡的表观线张力值为4.02×10 J/m 。 （注：原文中“4.02 × 10 J/m”这里的10后面应该少了指数，推测可能影响翻译的准确性，但按要求不做修改。）
