Manoranjan Narmadha, Zhang Feng, Wang Zhenyi, Dong Yanping, Fang Wangxi, Zhang Yatao, Zhu Yuzhang, Jin Jian
i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, P.R. China.
College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P. R. China.
ACS Appl Mater Interfaces. 2020 Nov 25;12(47):53096-53103. doi: 10.1021/acsami.0c14825. Epub 2020 Nov 10.
Covalent organic framework (COF)-based membranes are burgeoning candidates for separation technologies owing to their well-ordered channel structures. The exponential interest in the stability of the COF membrane on exposure to harsh organic solvents is directed to develop a composite membrane for dye separations in polar aprotic solvents. Here, we reported a nanocomposite membrane composing of a single-walled carbon nanotube (SWCNT)/COF (an imine-based COF) hybrid on a commercial polytetrafluoroethylene (PTFE) substrate, with a thickness of ∼58 nm prepared in a diffusion cell. This membrane displayed high permeability and stability toward nonpolar and aprotic solvents. It exhibited high permeability for lower viscous organic solvents such as hexane (66 L m h bar), acetone (60 L m h bar), and acetonitrile (59 L m h bar) with a desirable dye rejection (92.8% for Brilliant blue in acetone). The long-time operation demonstrated the excellent stability of the nanocomposite membrane. We herein reported a facile and mild method to prepare an ultrathin COF-based nanocomposite membrane with a porous, robust structure coupled with solvent durability capable of efficient dye separation.
基于共价有机框架（COF）的膜由于其有序的通道结构，正成为分离技术中新兴的候选材料。人们对COF膜在暴露于苛刻有机溶剂时的稳定性兴趣激增，旨在开发一种用于在极性非质子溶剂中进行染料分离的复合膜。在此，我们报道了一种在商用聚四氟乙烯（PTFE）基底上由单壁碳纳米管（SWCNT）/COF（一种基于亚胺的COF）杂化体组成的纳米复合膜，其厚度约为58 nm，是在扩散池中制备的。该膜对非极性和非质子溶剂表现出高渗透性和稳定性。它对低粘度有机溶剂如己烷（66 L m⁻² h⁻¹ bar⁻¹）、丙酮（60 L m⁻² h⁻¹ bar⁻¹）和乙腈（59 L m⁻² h⁻¹ bar⁻¹）具有高渗透性，并且对染料具有理想的截留率（在丙酮中对亮蓝的截留率为92.8%）。长时间运行证明了该纳米复合膜具有出色的稳定性。我们在此报道了一种简便温和的方法来制备具有多孔、坚固结构以及溶剂耐久性的超薄COF基纳米复合膜，该膜能够高效地进行染料分离。
