High CO2 uptake capacity and selectivity in a N-oxide-functionalized 3D Ni(II) microporous metal–organic framework

• Published in: Polyhedron Vol. 193; p. 114839
• Main Author: Zhang, Wen-Qian
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-01-2021
• Subjects: Gas adsorption; Metal–organic framework; Open donor sites; Selectivity; Metal–organic framework; Selectivity; Gas adsorption; Open donor sites
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2020.114839

A 3D rigid porous Ni(II) Metal−Organic Framework has been synthesized, possessing 1D diamond channels decorated with N-Oxide “open donor sites” (ODSs) and carboxylic sites. The gas adsorption behavior of this framework exhibit high capacity and selectivity of CO2 over CH4.
[Display omitted]
•The pyridine-N-O ligand possess superior characteristics than pyridine-N ligand.•A 3D rigid N-O functional porous Ni(II) MOF possesses 1D diamond channels.•There exist abundant N-Oxide “open donor sites” and vacant carboxyl sites.•The gas adsorption behavior shows high capacity and selectivity for CO2 over CH4.
A three-dimensional (3D) rigid Ni(II) microporous metal–organic framework (MOF), {[Ni(bpdado)(bpe)(H2O)2]·2DMF·2H2O}n (1), has been synthesized upon axially chiral N-Oxide-functionalized 2,2′-bipyridine-3,3′-dicarboxylate-1,1′-dioxide (H2bpdado) ligand with auxiliary rigid linear trans-1,2-bis (4-pyridyl)ethene (bpe) linker. Structural analysis reveals that there exist 1D diamond channels in the framework of 1, decorated with abundant N-Oxide “open donor sites” (ODSs) and vacant carboxyl sites on the pore surfaces. The modification of pyridine-N into the N-oxide group endows the N-oxide group with unique charge-separated plus electron-rich character, which may provide an enhanced affinity towards CO2 molecules. The gas adsorption property of 1' has been investigated by N2, CH4 and CO2, and it exhibits a high capacity and selectivity for CO2 over CH4.