Abstract Gas separation by metal-organic framework (MOF) membranes are still unsatisfactory due partly to unsatisfied separation characteristics caused by the trade-off between selectivity and permeability. Herein, we provide a facile post CO 2 annealing method to remarkably improve both the permeance and separation factor of IRMOF-1 membranes for CO 2 separation from CO 2 /H 2 mixture. Post-treatment of the IRMOF-1 membrane by annealing at 100 °C under a high pressure CO 2 stream deceases H 2 permeance while increasing CO 2 permeance, leading to simultaneous enhancement in both CO 2 /H 2 separation factor from 721 up to 5781 and CO 2 permeance from 5.67 × 10 −7 up to 9.38 × 10 −7 mol m −2 s −1 Pa −1 at CO 2 molar fraction of 98%, feed pressure of 5 atm and 298 K. The unusual separation behavior is related to the enhanced CO 2 adsorption selectivity over H 2 and reduced CO 2 affinity of the membrane due to the formation of surface carbonate anions caused by the CO 2 treatment. The proposed gas atmosphere post-treatment strategy opens a window for designing next generation MOF-related gas separation membranes.

中文翻译：

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通过 CO 2 退火后处理的高 CO 2 渗透选择性金属有机骨架膜

摘要 金属有机骨架 (MOF) 膜的气体分离仍然不令人满意，部分原因是选择性和渗透性之间的权衡导致分离特性不令人满意。在此，我们提供了一种简便的 CO 2 后退火方法，以显着提高 IRMOF-1 膜的渗透率和分离系数，用于从 CO 2 /H 2 混合物中分离 CO 2。通过在高压 CO 2 流下在 100 °C 下退火对 IRMOF-1 膜进行后处理，降低了 H 2 渗透性，同时增加了 CO 2 渗透性，从而同时将 CO 2 /H 2 分离因子从 721 提高到 5781在 CO 2 摩尔分数为 98%、进料压力为 5 atm 和 298 K 时，CO 2 渗透率从 5.67 × 10 -7 到 9.38 × 10 -7 mol m -2 s -1 Pa -1。不寻常的分离行为与CO 2 对H 2 的吸附选择性增强以及由于CO 2 处理导致表面碳酸根阴离子的形成而降低的膜的CO 2 亲和力有关。拟议的气体气氛后处理策略为设计下一代 MOF 相关气体分离膜打开了一扇窗。