Tailorable Multi‐Modular Pore‐Space‐Partitioned Vanadium Metal‐Organic Frameworks for Gas Separation
Wei Wang, Yichong Chen, Pingyun Feng, Xianhui Bu
Abstract
Abstract Currently, few porous vanadium metal‐organic frameworks (V‐MOFs) are known and even fewer are obtainable as single crystals, resulting in limited information on their structures and properties. Here this work demonstrates remarkable promise of V‐MOFs by presenting an extensible family of V‐MOFs with tailorable pore geometry and properties. The synthesis leverages inter‐modular synergy on a tri‐modular pore‐partitioned platform. New V‐MOFs show a broad range of structural features and sorption properties suitable for gas storage and separation applications for C 2 H 2 /CO 2 , C 2 H 6 /C 2 H 4 , and C 3 H 8 /C 3 H 6 . The c / a ratio of the hexagonal cell, a measure of pore shape, is tunable from 0.612 to 1.258. Other tunable properties include pore size from 5.0 to 10.9 Å and surface area from 820 to 2964 m 2 g −1 . With C 2 H 2 /CO 2 selectivity from 3.3 to 11 and high uptake capacity for C 2 H 2 from 65.2 to 182 cm 3 g −1 (298K, 1 bar), an efficient separation is confirmed by breakthrough experiments. The near‐record high uptake for C 2 H 6 (166.8 cm 3 g −1 ) contributes to the promise for C 2 H 6 ‐selective separation of C 2 H 6 /C 2 H 4 . The multi‐module pore expansion enables transition from C 3 H 6 ‐selective to more desirable C 3 H 8 ‐selective separation with extraordinarily high C 3 H 8 uptake (254.9 cm 3 g −1 ) and high separation potential (1.25 mmol g −1 ) for C 3 H 8 /C 3 H 6 (50:50 v/v) mixture.