Induced Fit of C₂H₂ in a Flexible MOF Through Cooperative Action of Open Metal Sites

Abstract

Porous materials that can undergo pore‐structure adjustment to better accommodate specific molecules are ideal for separation and purification. Here, we report a stable microporous metal‐organic framework, JNU‐1, featuring one‐dimensional diamond‐shaped channels with a high density of open metal sites arranged on the surface for the cooperative binding of acetylene. Together with its framework flexibility and appropriate pore geometry, JNU‐1 exhibits an induced‐fit behavior for acetylene. The specific binding sites and continuous framework adaptation upon increased acetylene pressure are validated by molecular modeling and in situ X‐ray diffraction study. This unique induced‐fit behavior endows JNU‐1 with an unprecedented increase in the acetylene binding affinity (adsorption enthalpy: up to 47.6 kJ mol−1 at ca. 2.0 mmol g−1 loading).

Boosting the C2H2/CO2 Separation Performance of Metal–Organic Frameworks through Fluorine Substitution

“…Metal–organic frameworks (MOFs), also called porous coordination polymers, formed by metal-based nodes and bridging organic ligands through coordination bonds are a kind of porous solid materials with long-ordered structures and high porosity . The intrinsic porous characteristics make MOFs great promising potentials in gas storage and separation . By varying the inorganic and organic components, diverse MOFs with desirable physical properties and fascinating structures can be achieved .…”

A chemically stable nanoporous coordination polymer with fixed and free Cu2+ ions for boosted C2H2/CO2 separation

“…In addition, the selectivity decreases gradually with increasing pressure, where the values are 14.8 (1:4, v/v) and 10.2 (1:1, v/v) at 0.15 bar, a pressure that usually represents the gas ratio of CO2 and C2H2 concentrations in industry. Further comparison shows that the C2H2/CO2 selectivity of NTU-66-Cu at 0.15 bar is lower than that of the benchmark material of NKMOF-1-Ni (~ 39) [42], but much higher than that of a series of important PCPs, including TIFSIX-2-Cu-i (6.2) [43], FJU-90 (4.3) [44], and JNU-1 (4.5) [45]. Therefore, the values of the selectivity reflect that NTU-66-Cu possesses significantly improved characteristic to address the challenging C2H2/CO2 separation compared with that of NTU-66.…”

“…In contrast, reactivation of NKMOF-1 requires faster He flow (30 mL•min −1 ), as well higher temperature (90 °C) and longer time (10 h) [46]. Furthermore, the sample regeneration of C2H2-adsorbed JNU-1 requires higher regeneration temperature (120 °C, 2 h), otherwise, the capacity of C2H2 decreases during the cycle measurements [45]. Therefore, NTU-66-Cu is one of the promising candidates for feasible C2H2/CO2 separation, since it has good structural stability, nearly intact capability, and also energy-saved regeneration process.…”

Rational Construction of Ultrahigh Thermal Stable MOF for Efficient Separation of MTO Products and Natural Gas

“…As shown in Figure d, the Q st values followed the hierarchy of C 3 > C 2 > CH 4 , conferring the potential of separating C 1 /C 2 /C 3 alkanes and C 2 /C 3 alkenes. The Q st values gradually increase for C 3 H 6 and C 3 H 8 at higher coverage, differing from the cases of C 2 H 6 , C 2 H 6 , and CH 4 , implying the C 3 adsorption benefits from the intermolecular interactions among the adsorbates. − Further, continuous C 2 H 4 adsorption/desorption tests confirm easy recyclability of Zn-BPZ-SA with no capacity loss (Figure S12).…”