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Abstract Isoreticular chemistry, which enables property optimization by changing compositions without changing topology, is a powerful synthetic strategy. One of the biggest challenges facing isoreticular chemistry is to extend it to ligands with strongly coordinating substituent groups such as unbound −COOH, because competitive interactions between such groups and metal ions can derail isoreticular chemistry. It is even more challenging to have an isoreticular series of carboxyl‐functionalized MOFs capable of encompassing chemically disparate metal ions. Here, with the simultaneous introduction of carboxyl functionalization and pore space partition, a family of carboxyl‐functionalized materials is developed in diverse compositions from homometallic Cr3+and Ni2+to heterometallic Co2+/V3+, Ni2+/V3+, Co2+/In3+, Co2+/Ni2+. Cr‐MOFs remain highly crystalline in boiling water. Unprecedentedly, one Cr‐MOF can withstand the treatment cycle with 10mNaOH and 12mHCl, allowing reversible inter‐conversion between unbound −COOH acid form and −COO−base form. These materials exhibit excellent sorption properties such as high uptake capacity for CO2(100.2 cm3 g−1) and hydrocarbon gases (e.g., 142.1 cm3 g−1for C2H2, 110.5 cm3 g−1for C2H4) at 1 bar and 298K, high benzene/cyclohexane selectivity (up to ≈40), and promising separation performance for gas mixtures such as C2H2/CO2and C2H2/C2H4.
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This content will become publicly available on January 1, 2026
Ligand Circuit Concept for Developing Gas Separation Materials from Pore‐Space‐Partitioned Metal‐Organic Frameworks
Abstract Isoreticular chemistry is among the most powerful strategies for designing novel materials with optimizable pore geometry and properties. Of great significance to the further advance of isoreticular chemistry is the development of broadly applicable new concepts capable of guiding and systematizing the ligand‐family expansion as well as establishing correlations between dissimilar and seemingly uncorrelated ligands for better predictive synthetic design and more insightful structure and property analysis. Here ligand circuit concept is proposed and its use has been demonstrated for the synthesis of a family of highly stable, high‐performance pore‐space‐partitioned materials based on an acyclic ligand,trans,trans‐muconic acid. This work represents a key step toward developing highly porous and highly stable pore‐space‐partitioned materials from acyclic ligands. The new materials exhibit excellent sorption properties such as high uptake capacity for CO2(81.3 cm3 g−1) and C2H2(165.4 cm3 g−1) by CPM‐7.3a‐NiV. CPM‐7.3a‐CoV shows C2H6‐selective C2H6/C2H4separation properties and its high uptakes for C2H4(134.0 cm3 g−1) and C2H6(148.0 cm3 g−1) at 1 bar and 298 K contribute to the separation potential of 1.35 mmol g−1. The multi‐cycle breakthrough experiment confirms the promising separation performance for C2H2/CO2.
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- Award ID(s):
- 2105961
- PAR ID:
- 10637182
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Small
- Volume:
- 21
- Issue:
- 4
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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