Abstract:
Highly flexible and robust self-standing covalent organic framework (COF) membranes with rapid preparation are important but technically challenging for achieving precise separation. Herein , a novel imine-based 2D soft covalent organic framework (SCOF) membrane with a large area of 226.9 cm2 , via ingeniously selecting an aldehyde flexible linker and a trigonal building block, is reported. The soft 2D covalent organic framework membrane is rapidly formed (≈5 min) based on the sodium dodecyl sulfate (SDS) molecular channel constructed at the water/dichloromethane (DCM) interface, which is the record-fast SCOF membrane formation and 72 times faster than that in the reported literature. MD simulation and DFT calculation elucidate that the dynamic, self-assembled SDS molecular channel facilitates faster and more homogeneous transfer of amine monomers in the bulk, thereby forming a soft 2D self-standing COF membrane with more uniform pores. The formed SCOF membrane exhibits superb sieving capability for small molecules, robustness in strong alkaline (5 mol L-1 NaOH), acid (0.1 mol L-1 HCl), and various organic solutions, and sufficient flexibility with a large curvature of 2000 m-1 for membrane-based separation science and technology.
摘要:
具有快速制备的高度柔性和坚固的自支撑共价有机骨架(COF)膜对于实现精确分离是重要的,但在技术上具有挑战性。在这一贡献中,我们首先报告了一种新颖的基于亚胺的2D软共价有机框架(SCOF)膜,该膜具有226.9cm2的大面积,通过巧妙地选择醛柔性接头和三角形结构单元。基于在水/二氯甲烷(DCM)界面构建的十二烷基硫酸钠(SDS)分子通道,快速形成软2D共价有机框架膜(约5分钟),这是创纪录的快速SCOF膜形成,比文献报道的快72倍。MD模拟和DFT计算阐明了动态,自组装SDS分子通道促进胺单体在本体中更快、更均匀的转移,从而形成具有更均匀孔隙的软2D自立式COF膜。形成的SCOF膜对小分子表现出极好的筛分能力,在(I)强碱性(5mol/LNaOH)中的稳健性,(二)酸(0.1mol/LHCl),和(III)各种有机溶液,和足够的灵活性,具有2000m-1的大曲率,用于膜分离科学技术。本文受版权保护。保留所有权利。