Synthesis and structural elucidation of neutral N-donor linker based bi-porous isostructural cationic metal-organic frameworks

Abstract

Two novel two-dimensional cationic metal-organic frameworks, namely iMOF-27-Co and iMOF-27-Ni, have been synthesized at room temperature by using a prefunctionalized anhydride core based neutral N-donor ligand. Single crystal X-ray diffraction (SC-XRD) study revealed that both compounds crystallizes in the orthorhombic space group Cmcm with molecular formula {[Co1(L)2(DMF)2](ClO4)2.x·(G)}n, {[Ni1(L)2(DMF)2](ClO4)2.x·(G)}n (L = ligand, x·G = disordered guest molecules) respectively. Powder X-ray diffraction (PXRD) patterns reveals that all the aforementioned MOFs are isostructural in nature. Further, both the MOFs exhibited an efficient carbon dioxide (CO2) uptake over N2 at both low and room temperature. High isosteric heat of adsorption (Qst) has been obtained for both compounds because of strong interactions between the polar groups of the framework and CO2 molecules.