Single-Phase Covalent Organic Framework Staggered Stacking Nanosheet Membrane for CO2 -Selective Separation.
Single-Phase Covalent Organic Framework Staggered Stacking Nanosheet Membrane for CO2 -Selective Separation.
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DOI：
10.1002/anie.202106346
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发表时间：
2021-07
影响因子：
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通讯作者：
Pengyuan Wang;Yuan Peng;Chenyu Zhu;Rui Yao;Hongling Song;Lun Kun;Weishen Yang
中科院分区：
文献类型：
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作者：
Pengyuan Wang;Yuan Peng;Chenyu Zhu;Rui Yao;Hongling Song;Lun Kun;Weishen Yang
二维共价有机骨架（2D COF）被认为是气体分离膜的潜在候选者，受益于永久孔隙率、轻质骨架、优异的稳定性和易于定制的功能。然而，它们的孔径通常大于普通气体分子的动力学直径。一个巨大的挑战是单相COF膜的制造，以实现精确的气体分离。在此，开发了三种具有不同孔径的高质量β-酮胺型COF纳米片，并将其聚集成具有独特的交错堆叠图案的纳米片膜。COF膜的微结构导致的孔径变窄和选择性吸附能力的协同作用赋予了COF膜有趣的亲CO2分离性能，其中中等孔径的TpPa-2在298 K下表现出最佳的CO2/H2分离因子为22，CO2渗透率为328个气体渗透单位。该膜的性能达到了目标，具有用于合成气分离的商业可行性。
Two-dimensional covalent organic frameworks (2D COFs) are considered as potential candidates for gas separation membranes, benefiting from permanent porosity, light-weight skeletons, excellent stability and facilely-tailored functionalities. However, their pore sizes are generally larger than the kinetic diameters of common gas molecules. One great challenge is the fabrication of single-phase COF membranes to realize precise gas separations. Herein, three kinds of high-quality β-ketoenamine-type COF nanosheets with different pore sizes were developed and aggregated to ultrathin nanosheet membranes with distinctive staggered stacking patterns. The narrowed pore sizes derived from the micro-structures and selective adsorption capacities synergistically endowed the COF membranes with intriguing CO2 -philic separation performances, among which TpPa-2 with medium pore size exhibited an optimal CO2 /H2 separation factor of 22 and a CO2 permeance of 328 gas permeation units at 298 K. This membrane performance reached the target with commercial feasibility for syngas separations.