Porous metal–organic frameworks with high stability and selective sorption for CO2 over N2

Two new metal–organic frameworks {[Ni(L)2] ·4H2O}n (1) and {[Co(L)2]·4H2O}n (2) have been prepared by reactions of 3,5-di(pyridine-4-yl)benzoic acid (HL) with corresponding metal salt under solvothermal conditions, and characterized by single crystal and powder X-ray diffractions, IR, elemental and thermogravimetric analyses. 1 and 2 have the same 2-fold interpenetrating three-dimensional structure with ins topology and are porous frameworks upon desolvation. More importantly, the desolvated samples of 1 and 2 show high thermal stability, vapor adsorption of H2O, MeOH or EtOH, and high enthalpy for CO2 adsorption and high selectivity for CO2 over N2 at 298 K, implying the potential application of the coordination polymers for capture and separation of CO2.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Porous metal–organic frameworks with ins topology. ► High thermal stability and high enthalpy for CO2 adsorption. ► Selective sorption behavior of CO2 over N2 at 298 K.