Li Shuo, Sun Yu-Jie, Wang Zhao-Xu, Jin Cheng-Gang, Yin Ming-Jie, An Quan-Fu
Beijing Key Laboratory for Green Catalysis and Separation, Department of Chemical Engineering, Beijing University of Technology, Beijing, 100124, P. R. China.
Small. 2023 May;19(19):e2208177. doi: 10.1002/smll.202208177. Epub 2023 Jan 30.
Mixed matrix membranes (MMMs), conjugating the advantages of flexible processing-ability of polymers and high-speed mass transfer of porous fillers, are recognized as the next-generation high-performance CO capture membranes for solving the current global climate challenge. However, controlling the crystallization of porous metal-organic frameworks (MOFs) and thus the close stacking of MOF nanocrystals in the confined polymer matrix is still undoable, which thus cannot fully utilize the superior transport attribute of MOF channels. In this study, the "confined swelling coupled solvent-controlled crystallization" strategy is employed for well-tailoring the in-situ crystallization of MOF nanocrystals, realizing rapid (<5 min) construction of defect-free freeway channels for CO transportation in MMMs due to the close stacking of MOF nanocrystals. Consequently, the fabricated MMMs exhibit approximately fourfold enhancement in CO permeability, i.e., 2490 Barrer with a CO /N selectivity of 37, distinctive antiplasticization merit, as well as long-term running stability, which is at top-tier level, enabling the large-scale manufacture of high-performance MMMs for gas separation.
混合基质膜（MMMs）结合了聚合物灵活的加工能力和多孔填料的高速传质优势，被认为是解决当前全球气候挑战的下一代高性能CO₂捕集膜。然而，控制多孔金属有机框架（MOFs）的结晶，进而控制MOF纳米晶体在受限聚合物基质中的紧密堆积仍然无法实现，因此无法充分利用MOF通道卓越的传输特性。在本研究中，采用“受限溶胀耦合溶剂控制结晶”策略对MOF纳米晶体的原位结晶进行精细调控，由于MOF纳米晶体的紧密堆积，实现了在MMMs中快速（<5分钟）构建无缺陷的CO₂传输高速公路通道。因此，制备的MMMs的CO₂渗透率提高了约四倍，即达到2490 Barrer，CO₂/N₂选择性为37，具有独特的抗增塑性能以及顶级水平的长期运行稳定性，可以大规模制造用于气体分离的高性能MMMs。
