Sun Zhenning, Cao Zhengyu, Li Yan, Zhang Qiuya, Zhang Xiaofang, Qian Jiangang, Jiang Lei, Tian Dongliang
Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Chemistry, Beihang University, Beijing 100191, P. R. China.
School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, P. R. China.
Mater Horiz. 2022 Feb 7;9(2):780-790. doi: 10.1039/d1mh01820e.
Controllable liquid transportation through a smart porous membrane is realized by manipulating the surface wetting properties and external stimuli, and has been intensively studied. However, the liquid transportation, , permeation and moving process, at the interface is generally uninterrupted, , the opening and closing of the interface is irreversible. Herein, we present a new strategy to achieve magnetic adaptive switchable surfaces, , liquid-infused micro-nanostructured porous composite film surfaces, for controllable liquid transportation, modulation of the magnetic field. The liquid transportation process can be interrupted and restarted on the porous composite film because its pore structure can be quickly closed and opened owing to the adaptive morphological transformation of the magnetic liquid with a varying magnetic field. That is, the liquid permeation process occurs due to the open pore structure of the composite film when the external magnetic field is added, while the permeation process can be interrupted owing to the self-repairing closure of the pore when the magnetic field is removed, and the moving process can be achieved. Thus a magnetic field induced switchable porous composite film can serve as a valve to control liquid permeation based transportation, which opens new avenues for artificial liquid gating devices for flow, smart separation, and droplet microfluidics.
通过操控表面润湿性和外部刺激实现了通过智能多孔膜的可控液体传输，并且这一过程已得到深入研究。然而，在界面处的液体传输，即渗透和移动过程通常是不间断的，而且界面的打开和关闭是不可逆的。在此，我们提出一种新策略，以实现用于可控液体传输的磁自适应可切换表面，即注入液体的微纳米结构多孔复合膜表面，通过磁场调制来实现。在多孔复合膜上，液体传输过程可以被中断并重新开始，这是因为随着磁场变化，磁性液体的自适应形态转变能使复合膜的孔结构快速关闭和打开。也就是说，施加外部磁场时，复合膜开放的孔结构会导致液体渗透过程发生，而去除磁场时，孔的自修复闭合会使渗透过程中断，进而实现移动过程。因此，磁场诱导的可切换多孔复合膜可作为一个阀门来控制基于液体渗透的传输，这为用于流体流动、智能分离和液滴微流控的人工液体门控装置开辟了新途径。
