A Multinary Metal–Organic Framework with Divided Linkers for C₂H₂/CO₂ Separation

Abstract

Developing porous solid adsorbents with strong interactions toward C2H2 is crucial to achieve C2H2/CO2 separation with high selectivity. Herein, we introduce the concept of “divided linkers” for the construction of metal–organic frameworks (MOFs) with tailored pores and well-positioned adsorption sites. A single CuI node divides the pyrazyl-carboxylate linker 4,4′-(2,6-pyrazinediyl)­dibenzoic acid into two equivalent edges. Furthermore, these edges reticulate with the pseudo-octahedral Zn-based building units to afford a porous multinary framework with single crystallinity and impressive chemical stability. Its appropriate pore size (6.4 Å) and high density of interacting sites empower the MOF with high capacity in C2H2 adsorption (104 cm3 g–1) and preferential C2H2 capture over CO2 (selectivity = 3.3) at 298 K. Potential use of the robust architecture for C2H2/CO2 separation is confirmed by the dynamic gas mixture breakthrough experiment.

Two Structurally Similar Co5 Cluster-Based Metal–Organic Frameworks Containing Open Metal Sites for Efficient C2H2/CO2 Separation

“…1 and 2 exhibited reversible microporous (type I) adsorption isotherms under N 2 adsorption at 77 K and 1 atm (Figure a,b). Pore size distribution (PSD) curves measured on the basis of DFT methods show that the main pore size distributions of both 1 and 2 are in the 6.8 Å permanent microporous channel (inset, Figure a,b), , but 1 and 2 have different pore morphologies due to the diversity of connection modes between the ligand and metal (Figure S3). The maximum nitrogen adsorption capacities of 1 and 2 are 220 and 261 cm 3 g –1 , respectively.…”

Porous functional metal–organic frameworks (MOFs) constructed from different N-heterocyclic carboxylic ligands for gas adsorption/separation

“…More recently, the team has introduced the concept of "divided linkers" to create a MOF with abundant pyrazyl N atomic sites. 115 Because of the particular pore environment, the MOF can adsorb large amounts of C 2 H 2 (104 cm 3 g −1 ) and selectively capture C 2 H 2 at 298 K with a selectivity of 3.3. A workable synthesis method to create MOFs with high gas storage and separation capabilities was suggested in this study.…”

Rational Synthesis of a Stable Rod MOF for Ultrasensitive Detection of Nitenpyram and Nitrofurazone in Natural Water Systems

“…24,25 In the progressive development of reticular chemistry, 26−28 most SBUs exist in isolated forms, such as mononuclear metal cations, 29 metalcarboxylate clusters, 30 or molecular building blocks. 31 ever, there is a class of MOFs in which SBUs are infinite in 1D. 32−35 They are referred to as rod SBUs.…”

“…Metal ions/clusters as the secondary building units (SBUs) in periodic frameworks provide the possibility to modulate the physicochemical properties of MOFs. , In the progressive development of reticular chemistry, − most SBUs exist in isolated forms, such as mononuclear metal cations, metal-carboxylate clusters, or molecular building blocks . However, there is a class of MOFs in which SBUs are infinite in 1D. − They are referred to as rod SBUs. − Typically, rod MOFs possess a 1D pore structure and remarkable stability advantages (such as MIL-53, MOF-74, and UTSA-30).…”