Two isostructural metal–organic frameworks with unique nickel clusters for C2H2/C2H6/C2H4 mixture separation. Issue 23 (26th May 2022)

• Record Type: Journal Article
• Authors: Wang, Hao-Tian; Chen, Qiang; Zhang, Xin; Zhao, Yan-Long; Xu, Ming-Ming; Lin, Rui-Biao; Huang, Hongliang; Xie, Lin-Hua; Li, Jian-Rong
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 23(2022)
• Page Start: 12497
• Page End: 12502
• Publication Date: 2022-05-26
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d2ta01466a
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Two isostructural MOFs BUT-150 and BUT-151 with unique nickel clusters have been synthesized. The presence of open metal sites, large pi conjugation and appropriate pore size lead to efficient separation of the ternary C2 H2 /C2 H6 /C2 H4 mixture. Abstract : Novel metal clusters and coordinatively unsaturated sites are important features of metal–organic frameworks (MOFs) for many applications such as catalysis, gas storage and separation. Herein, two isostructural MOFs, BUT-150 and BUT-151 with unprecedented binuclear nickel clusters have been developed, using tetracarboxylate linkers containing chelating bipyridine-type units. The nickel cluster is coordinated with four carboxylate groups, one bipyridine unit, and one bridging water, leading to two open nickel sites per cluster. Interestingly, the two MOFs show selective adsorption of C2 H2 and C2 H6 over C2 H4, representing two rare examples of MOFs with open metal sites for such ternary separation. Especially, BUT-151 with a phenanthroline unit has a high C2 H2 /C2 H4 selectivity of 2.31 and C2 H6 /C2 H4 selectivity of 1.36 at 273 K, being higher or comparable to current benchmark materials. The overall good separation performance of BUT-151 may be attributed to its high acetylene affinity from open metal sites and efficient confinement of ethane molecules by the open window with rich oxygen sites. Column breakthrough experiments confirm the good separation performance of binary or ternary gas mixtures by BUT-151 under dynamic conditions.