Ultra-high adsorption selectivity and affinity for CO2 over CH4, and luminescent properties of three new solvents induced Zn(II)-based metal-organic frameworks (MOFs)

Herein, three new solvents induced metal-organic frameworks (MOFs), [Zn(H2L)H2O] (1), [Zn-2(L)H2O] (2) and [Zn-3(HL)(2)]-(CH3CN)(2) (3) were synthesized via the solvothermal reaction procedure by using a rigid v-shaped 3,5-di (2,4-dicarboxylphenyl)pyridine (H4L) and Zn(II) ions. Structural analyses show that the organic ligand H4L adopt various degrees deprotonation (H2L2- for 1; L4- for 2 and HL3- for 3), which obtain different structures for three new MOFs: 2D layer network for 1; 3D dense packing structure for 2 and 3D porous structure with the pore size of 10.3 x 10.6 angstrom(2) for 3. The gas sorption behavior of the guest-free phase 3' shows an ultra-high adsorption selectivity and affinity for CO2 over CH4. The experiment results provide us with a reasonable facile route for designing and synthesizing new potential gas sorption and separate materials in CO2 purification. And the solidstate luminescence properties of 1-3 were measured and studied intensively at room temperature.