A multifunctional cadmium-based metal-organic framework from a tricarboxylate ligand showing sensing and sensitization

Abstract

A luminescent-active cadmium-based 3D microporous metal-organic framework [Cd3 (cia)2 (4,4′-bipy) (H2O)2]n (MOF-1, H3cia ​= ​2-(4-carboxylphenoxy)terephthalic acid, 4,4′-bipy ​= ​4,4-bipyridine) was synthesized by choice of a V-shaped asymmetrical tricarboxylate ligand, exhibiting impressive high thermal stability and water stability. More importantly, it acts as luminescence sensor, showing highly selective and sensitive detection on nitrobenzene, Fe3+, Cr2O72− in aqueous solution by quenching effects. And the limit of detection (LOD) values of NB, Fe3+and Cr2O72− are 5.35 ​× ​10−5 ​M, 7.06 ​× ​10−5 ​M, 1.82 ​× ​10−5 ​M, respectively. Besides, MOF-1 can also exhibit the excellent antenna probing performance on Tb3+ ions through efficient energy transfer. In general, the excellent activities of optical-sensing, and sensitization properties for MOF-1 are attributed to active metal sites and accessible porous structure.