Ben Shuang, Zhou Tiantian, Ma Han, Yao Jinjia, Ning Yuzhen, Tian Dongliang, Liu Kesong, Jiang Lei
Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology, School of Chemistry Beihang University Beijing 100191 P. R. China.
State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 P. R. China.
Adv Sci (Weinh). 2019 Jul 15;6(17):1900834. doi: 10.1002/advs.201900834. eCollection 2019 Sep 4.
In nature, fluid manipulations are ubiquitous in organisms, and they are crucial for many of their vital activities. Therefore, this process has also attracted widescale research attention. However, despite significant advances in fluid transportation research over the past few decades, it is still hugely challenging to achieve efficient and nondestructive droplet transportation owing to contamination effects and controllability problems in liquid transportation applications. To this end, inspired by the motile microcilia of micro-organisms, the superhydrophobicity of lotus leaves, the underwater superoleophobicity of filefish skin, and pigeons' migration behavior, a novel manipulation strategy is developed for droplets motion. Specifically, herein, a superwettable magnetic microcilia array surface with a structure that is switchable by an external magnetic field is constructed for droplet manipulation. It is found that under external magnetic fields, the superhydrophobic magnetic microcilia array surface can continuously and directionally manipulate the water droplets in air and that the underwater superoleophobic magnetic microcilia array surface can control the oil droplets underwater. This work demonstrates that the nondestructive droplet transportation mechanism can be used for liquid transportation, droplet reactions, and micropipeline transmission, thus opening up an avenue for practical applications of droplet manipulation using intelligent microstructure surfaces.
在自然界中，流体操控在生物体中无处不在，并且对它们的许多重要活动至关重要。因此，这一过程也引起了广泛的研究关注。然而，尽管在过去几十年里流体运输研究取得了重大进展，但由于液体运输应用中的污染效应和可控性问题，实现高效且无损的液滴运输仍然极具挑战性。为此，受微生物的运动微纤毛、荷叶的超疏水性、翻车鱼皮肤的水下超疏油性以及鸽子的迁徙行为启发，开发了一种用于液滴运动的新型操控策略。具体而言，本文构建了一种具有可通过外部磁场切换结构的超润湿性磁性微纤毛阵列表面用于液滴操控。研究发现，在外部磁场作用下，超疏水磁性微纤毛阵列表面能够在空气中连续且定向地操控水滴，而水下超疏油磁性微纤毛阵列表面能够在水下控制油滴。这项工作表明，无损液滴运输机制可用于液体运输、液滴反应和微管道传输，从而为利用智能微结构表面进行液滴操控的实际应用开辟了一条途径。
