Two Cd(II)-Based MOFs Constructed from Tris(3′-F-4′-carboxybiphenyl)amine: Synthesis, Crystal Structure, Luminescence Sensing towards Nitrophenols and Acetylacetone

Abstract

Two new luminescent metal-organic frameworks (MOFs), namely [Cd4(TFBA)3(H2O)4]n (CdMOF-1) and [Cd(TFBA) (bipy)]n (CdMOF-2) (H3TFBA = tris(3′-F-4′-carboxybiphenyl)amine, 4,4′-bipy = 4,4’-bipyridine), have been prepared and successfully constructed via solvothermal conditions. Single-crystal structure analysis reveals that CdMOF-1 are two-dimensional network containing [Cd4O26] units. CdMOF-2 shows a non-interpenetration 3D microporous structure with a hexagon pore of 24.6 × 25.9 Å. Notably, CdMOF-2 exhibits turn off fluorescence behavior towards picric acid (TNP) and 4-Nitrophenol (PNP) with a limit of detection (LOD) value of 9.2 × 10−6 M and 1.81 × 10−5 M, respectively. Furthermore, CdMOF-2 shows obvious turn-on luminescence responses toward acetylacetone (Acac) with luminescence red-shift and a detection limit of 19.40 ppm. Additionally, the possible quenching or enhancing mechanism during the sensing process were evaluated by PXRD, UV-vis, and luminescence decay lifetime.