Cd(II) frameworks with tetracarboxylate and imidazole-containing ligands: Syntheses, structures, adsorption and sensing properties

Two novel metal-organic frameworks (MOFs) [Cd 2 (tib)(tpe)]·5DMA·H 2 O ( 1 ) and [Cd 4 (tipe) 2 (tpe) 2 ]·15CH 3 OH·11H 2 O ( 2 ) (DMA ​= ​ N , N -dimethylacetamide) were achieved by using cadmium(II) nitrate tetrahydrate to react with mixed multicarboxylate ligand of tetrakis(4-carboxyphenyl)ethene (H 4 tpe) and imidazole-containing one of 1,3,5-tris(1-imidazolyl)benzene (tib) or 1,1,2,2-tetrakis(4-(1-imidazolyl)phenyl)ethene (tipe) under solvothermal conditions. Both MOFs 1 and 2 have three-dimensional (3D) framework structures with distinct topologies. Due to the outstanding stability, porous structure and luminescence property, it was found that 1 can selectively adsorb gas molecules of CO 2 , light hydrocarbons as well as dye molecules of methyl orange (MO) and methyl blue (MB), and has selectivity for fluorescent sensing Fe 3+ . Cd(II) frameworks with 3D porous structures have been successfully fabricated by solvothermal reactions of Cd(II) salt with tetracarboxylate and imidazole-containing ligands. The frameworks show selectivity for sensing iron (III) ions and adsorbing gas and dye molecules. • 3D Cd(II) frameworks with mixed ligands were fabricated and characterized. • The Cd(II) frameworks show selectivity for fluorescent sensing Fe 3+ . • The porous frameworks can selectively adsorb gas and dye molecules.