Zhao Siyang, Liang Yongmin, Yang Yu, Huang Jinxia, Guo Zhiguang, Liu Weimin
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P. R. China.
University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
Nanoscale. 2021 Sep 23;13(36):15334-15342. doi: 10.1039/d1nr04658f.
Superhydrophobic and underwater superoleophobic surface combine the superiorities of the two opposite wettabilities. Generally, such a surface is constructed by hydrophilic areas and hydrophobic areas treated with fluorine-containing modifiers. However, the surface energy in a narrow range and poor bonding force between water-loving and water-repelling components make the surface fragile and its wettability unstable. Herein, we present a strategy to fabricate a robust surface with superhydrophobicity and underwater superoleophobicity. Hydrophilic aluminum phosphate as a binder can strongly interact with superhydrophobic titanium dioxide nanoparticles. Mixing the two ingredients to accurately control the surface energy in a narrow range and then spray coating, the superhydrophobic and underwater superoleophobic surfaces are conveniently prepared on diverse substrates. Under acid/base aqueous solution conditions, O-plasma etching, and sand impingement, the coatings remain superhydrophobic and underwater superoleophobic. Taking advantage of the wettability and robustness of coatings, the as-prepared membranes realize on-demand and multicycle separation under gravity without continuous external stimulus. Importantly, even after 100 sand impingement cycles, the treated membranes still maintain prominent separation performance.
超疏水和水下超疏油表面结合了两种相反润湿性的优势。一般来说，这样的表面是由用含氟改性剂处理过的亲水区和疏水区构成的。然而，窄范围内的表面能以及亲水和疏水组分之间较弱的结合力使得该表面易碎且其润湿性不稳定。在此，我们提出一种制备具有超疏水性和水下超疏油性的坚固表面的策略。亲水性磷酸铝作为粘合剂可与超疏水二氧化钛纳米颗粒强烈相互作用。将这两种成分混合以在窄范围内精确控制表面能，然后进行喷涂，即可在各种基材上方便地制备出超疏水和水下超疏油表面。在酸/碱水溶液条件、氧等离子体蚀刻和砂粒冲击下，涂层仍保持超疏水和水下超疏油性能。利用涂层的润湿性和坚固性，所制备的膜在重力作用下无需连续外部刺激即可实现按需和多循环分离。重要的是，即使经过100次砂粒冲击循环，处理过的膜仍保持出色的分离性能。
