Song Yuegan, Hu Yanlei, Zhang Yachao, Li Guoqiang, Wang Dawei, Yang Yi, Zhang Yafeng, Zhang Yiyuan, Zhu Wulin, Li Jiawen, Wu Dong, Chu Jiaru
School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China.
CAS Key Laboratory of Mechanical Behavior and Design of Materials, Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes, Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei 230026, P. R. China.
ACS Appl Mater Interfaces. 2022 Aug 17;14(32):37248-37256. doi: 10.1021/acsami.2c12890. Epub 2022 Aug 7.
Smart surfaces with tunable wettability are promising due to their abilities to create diversified functionalities that the fixed surfaces cannot provide. However, limited by imprecise adjustment of structural geometry and almost conventional switching modes of wettability, it is still challenging to achieve the reversible switching between multiple wetting states. Herein, a novel tri-switchable wettability surface with an in situ switching ability is used for the manipulation of a given droplet, which consists of a stretchable substrate and a micron column array. The femtosecond laser direct writing technique is utilized to generate distinct wettability of the two components. Taking the advantage of good tensile properties, the surface morphology is adjusted in a rapid, reversible way to obtain diverse wetting performances from the lotus-like effect to rice-leaf-like anisotropy and then to the rose-petal-like effect. Based on the triplex wetting transition on the same surface, we further developed a multifunctional device to realize a range of in situ manipulations, including the surface self-cleaning, the directional transport of droplets, and the capture, the vertical transport, and release of droplets. This work paves the way for expanding the field of smart surfaces with tunable wettability beyond conventional dual-property wetting behavior and exhibits versatile manipulations of droplets for microfluidic applications.
具有可调润湿性的智能表面很有前景，因为它们能够创造出固定表面无法提供的多种功能。然而，由于结构几何形状的调整不够精确以及润湿性几乎传统的切换模式的限制，实现多种润湿状态之间的可逆切换仍然具有挑战性。在此，一种具有原位切换能力的新型三可切换润湿性表面被用于操纵给定的液滴，它由一个可拉伸的基底和一个微米柱阵列组成。利用飞秒激光直写技术使这两个组件具有不同的润湿性。借助良好的拉伸性能，表面形态以快速、可逆的方式进行调整，以获得从荷叶效应到稻叶状各向异性再到玫瑰花瓣状效应的多种润湿性能。基于同一表面上的三重润湿转变，我们进一步开发了一种多功能装置，以实现一系列原位操作，包括表面自清洁、液滴的定向传输以及液滴的捕获、垂直传输和释放。这项工作为将具有可调润湿性的智能表面领域扩展到超越传统双特性润湿行为的范围铺平了道路，并展示了用于微流体应用的液滴的多功能操作。
