Optimized Pore Nanospace through the Construction of a Cagelike Metal–Organic Framework for CO<sub>2</sub>/N<sub>2</sub> Separation
Lei Zhang, Sihan Lin, Yupeng Liu, Xiayun Zeng, Jianjun You, Taotao Xiao, Yongjie Feng, Ziyu He, Song Chen, Nengbin Hua, Xiaoyun Ye, Zhang‐Wen Wei, Cheng‐Xia Chen
Abstract
The development of metal–organic framework (MOF) adsorbents with a potential molecule sieving effect for CO 2 capture and separation from flue gas is of critical importance for reducing the CO 2 emissions to the atmosphere yet challenging. Herein, a cagelike MOF with a suitable cage window size falling between CO 2 and N 2 and the cavity has been constructed to evaluate its CO 2 /N 2 separation performance. It is noteworthy that the introduction of coordinated dimethylamine (DMA) and N, N ′-dimethylformamide (DMF) molecules not only significantly reduces the cage window size but also enhances the framework–CO 2 interaction via C–H···O hydrogen bonds, as proven by molecular modeling, thus leading to an improved CO 2 separation performance. Moreover, transient breakthrough experiments corroborate the efficient CO 2 /N 2 separation, revealing that the introduction of DMA and DMF molecules plays a vital role in the separation of a CO 2 /N 2 gas mixture.