Metal Effects on the Framework Stability and Adsorption Property of a Series of Isoreticular Metal-Organic Frameworks Based on an in-Situ Generated T-Shaped Ligand

摘要

An in situ approach has been undertaken to synthesize a series of metal-organic frameworks (MOFs) with the pore surface functionalized via the organic linkers of multi N-heterocycles. This was done so as to explore their stability, flexibility, and adsorption behaviors on the basis of the nature of metal centers (M = Zn, Mg, Co, Ni). Four isoreticular MOFs based on in situ synthesized T-shaped ligands were obtained, and their phase purity and stability were investigated in conjunction with the adsorption properties for a wide range of gases (Ar, N-2, H-2, CO2, CH4, C2H6, C2H4, C3H8, and C3H6). The results revealed that the stability of MOF based on Ni2+ is better than those of Mg, Zn, and Co analogues, and that the multi N-heterocycles ligand endows these MOFs with higher affinity for CO2, C2H6, C2H4, C3H8, and C3H6, leading to an excellent selectivity for these gases over CH4.