Investigation of Gas Adsorption Performances and H₂ Affinities of Porous Metal-Organic Frameworks with Different Entatic Metal Centers

Three isomorphous porous metal-organic frameworks (MOFs; PCN-9 (Co/Fe/Mn)) with entatic metal centers have been constructed on the basis of the trigonal planar H₃TATB ligand and a novel square-planar secondary building unit. N₂ adsorption isotherms at 77 K confirmed the permanent porosities of the three porous MOFs. Variable-temperature adsorption measurements of H₂ revealed that the H₂ affinities of the three porous MOFs are related to the nature of entatic metal centers, which reversely affect their H₂ uptake capacities.