A Robust Multifunctional Eu6-Cluster Based Framework for Gas Separation and Recognition of Small Molecules and Heavy Metal Ions

We report a multifunction lanthanide-based metal organic framework (Eu-SPFF) constructed by a hexanuclear Eu(III) cluster and a tetracarboxylate ligand 4,4′,4″,4‴-(9,9′-spirobi[fluorene]-2,2′,7,7′-tetrayl)tetrakis(2-fluorobenzoic acid) (H4SPFF). The (4,12)-connected ftw topological three-dimensional structure contains octahedral and cubic cages with permanent porosity (BET: 1891.3 m2 g–1). Eu-SPFF not only exhibits high performance for the separation of light hydrocarbons but also shows highly selective recognition of 4-nitrophenol and Cu2+ ions.