State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, No. 122, Luoshi Road, Wuhan 430070, PR China.
School of Energy and Power Engineering, Jiangsu University, No.301, Xuefu Road, Zhenjiang 212013, PR China.
J Colloid Interface Sci. 2021 Oct 15;600:118-126. doi: 10.1016/j.jcis.2021.05.004. Epub 2021 May 5.
Due to the inherent differences in surface tension between water and oil, it is a challenge to fabricate air superhydrophilic-superoleophobic materials despite their promising potential in the field of oil/water separation. Herein, a facile approach is developed to fabricate air superhydrophilic-superoleophobic SiO coating by combination of controllable modifying SiO nanoparticle surface by both hydrophilic groups (i.e., -OH groups) and oleophobic groups (i.e., fluorinated groups) with constructing porous and hierarchical structures. Hydroxyl-modified SiO nanoparticles (NPs) are synthesized using a base-catalysed procedure in the presence of ammonia or NaOH. Chitosan quaternary ammonium salt (HACC) is introduced to bind SiO by forming a unique hydrogen bond between HACC and -OH, followed by adding pentadecafluorooctanoic acid (PFOA) to complex with HACC to form fluorinated groups. The SiO coatings are fabricated on various substrates (e.g., glass, foam and Cu mesh) by spraying procedure and characterized using SEM, FTIR, XPS, etc. The contact angles of oils (e.g., pump oil, castor oil, corn oil, hexadecane and bean oil) and water on the coatings are over 150° and close to 0°, respectively. By optimization, the representative SiO-coated Cu mesh displayed high-efficiency of 99.2% in separating water from mixture of water/pump oil, and high penetration flux of 1.41 × 10 L·m ·h. Besides, the coating maintains its superhydrophilic-superoleophobic properties even after 110 cycles of sandpaper abrasion or after being immersed in water for 3 h. After 20 cycles of oil/water separation, the coating retains separation efficiency up to 97.93%. This study provides a new and universal protocol to fabricate unique superwetting surfaces with effective oil/water separation performance, long-term durability and outstanding reusability.
由于水和油之间固有的表面张力差异，尽管在油水分离领域具有广阔的应用前景，但制造空气超亲水-超疏油材料仍然具有挑战性。在此，通过同时对亲水性（例如-OH 基团）和疏油性（例如氟基团）修饰的 SiO 纳米颗粒表面进行控制，并构建多孔和分级结构，开发了一种简便的方法来制备空气超亲水-超疏油 SiO 涂层。使用氨或 NaOH 存在下的碱催化法合成了羟基修饰的 SiO 纳米颗粒（NPs）。壳聚糖季铵盐（HACC）被引入以通过 HACC 和-OH 之间形成独特的氢键与 SiO 结合，然后添加全氟辛酸（PFOA）与 HACC 络合形成氟基团。通过喷涂程序在各种基底（例如玻璃、泡沫和 Cu 网）上制备 SiO 涂层，并使用 SEM、FTIR、XPS 等进行表征。涂层对油（例如，泵油、蓖麻油、玉米油、十六烷和豆油）和水的接触角分别超过 150°和接近 0°。通过优化，具有代表性的 SiO 涂覆的 Cu 网在分离水/泵油混合物时显示出 99.2%的高效率，并且具有 1.41×10 L·m·h 的高透过通量。此外，即使经过 110 次砂纸磨损或在水中浸泡 3 小时后，涂层仍保持超亲水-超疏油性能。在进行 20 次油水分离循环后，涂层仍保持高达 97.93%的分离效率。本研究提供了一种新的通用方案，用于制造具有有效油水分离性能、长期耐久性和出色可重复使用性的独特超润湿表面。
