Enhanced isosteric heat, selectivity, and uptake capacity of CO2 adsorption in a metal-organic framework by impregnated metal ions

We demonstrate by experimental and theoretical studies that the impregnation of various metal ions such as Li+, Mg2+, Ca2+, Co2+, and Ni2+ in the pores of an anionic MOF, [Zn-3(TCPT)(2)(HCOO)][NH2(CH3)(2)] (SNU-100') significantly enhances isosteric heat, selectivity, and uptake capacity of the CO2 adsorption in the MOF. Due to the electrostatic interactions between CO2 and the extra-framework metal ions, the isosteric heats of CO2 adsorption are increased to 37.4-34.5 kJ mol(-1) and the adsorption selectivities of CO2 over N-2 at room temperature are increased to 40.4-31.0, compared with those (29.3 kJ mol(-1) and 25.5, respectively) of the parent MOF (SNU-100') containing [NH2(CH3)(2)](+) cations.