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

A new three-dimensional (3D) porous Mn(II)-based metal-organic framework [Mn-4(L)(2)(H2O)(4)](n) center dot 4DMF center dot 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 x 8.8 angstrom(2) and 10.7 x 8.7 angstrom(2)). 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.