Ultrathin ionic COF Membrane via Polyelectrolyte‐Mediated Assembly for Efficient CO<sub>2</sub> Separation
Shao-Yu Wang, Yuhan Yang, Xu Liang, Yanxiong Ren, Hanze Ma, Ziting Zhu, Jianyu Wang, Shichen Zeng, Shuqing Song, Xuerui Wang, You Han, Guangwei He, Zhongyi Jiang
Abstract
Abstract Fabricating ultrathin covalent organic framework (COF) membranes toward high‐permeance molecular separations is highly desired yet challenging. Herein, a polyelectrolyte‐mediated assembly (PMA) strategy is developed to fabricate ultrathin ionic COF membrane for efficient CO 2 separation. The PMA strategy allows a facile control over the assembly mode between polyethyleneimine (PEI) and TpPa‐SO 3 H, yielding PEI‐bridged ultra‐large COF nanosheets which are readily processed into COF membranes with thickness down to 8 nm. The resulting COF membranes exhibit a high CO 2 permeances of 1371 GPU and CO 2 /N 2 selectivity of 33 for stimulated flue gas. This PMA strategy may open up a new avenue to fabricating ultrathin 2D material membranes for diverse applications.