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Title: Ultrastable Carboxyl‐Functionalized Pore‐Space‐Partitioned Metal‐Organic Frameworks for Gas Separation
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.  more » « less
Award ID(s):
2117040
PAR ID:
10556496
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Materials
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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