New multifunctional 3D porous metal–organic framework with selective gas adsorption, efficient chemical fixation of CO2 and dye adsorption

Abstract

A new three-dimensional (3D) porous Mn(II)-based metal–organic framework [Mn₄(L)₂(H₂O)₄]_n·4DMF·H₂O (1) has been synthesized using Mn(II) and the rigid 2,6-di(2′,5′-dicarboxylphenyl)pyridine (H₄L) ligand under solvothermal conditions. Structural analysis revealed that MOF 1 is an open framework with exposed active nitrogen atoms and rectangular-shaped channels along the b axis (with effective aperture sizes of 11.3 × 8.8 Ų and 10.7 × 8.7 Ų). Gas sorption behaviors showed that MOF 1 has a relatively high capacity and selectivity for CO₂ over CH₄. Thus, the CO₂ cycloadditions were studied using different epoxides, displaying the high efficiency of the catalyst. It was also found that MOF 1 shows rapid adsorption for the organic dyes. Therefore, MOF 1 should be explored as a multifunctional porous material for gas separation, catalysis and dye adsorption.