Three-dimensional terbium(III) metal–organic framework constructed by thiophene-2,5-dicarboxylate: synthesis, crystal structure and fluorescent properties

A novel Tb(III) metal–organic framework was synthesized by a multi-layer diffusion method at room temperature. Adjacent Tb(III) ions were connected together by bridging carboxylic groups to construct one-dimensional chains and the metal–organic framework based on these parallel 1D chains was formed through thiophene-2,5-dicarboxylate bridges. UV–Vis and fluorescent emission spectra as well as theoretical calculation showed that organic ligands acted as sensitizers to Tb(III) fluorescence. With the excitation of 325 nm, the emission peaks of this compound were found at 488, 545, 587, and 621 nm which were attributed to 5 D 4 → 7 F 6 , 5 D 4 → 7 F 5 , 5 D 4 → 7 F 4 , and 5 D 4 → 7 F 3 transitions, respectively. The quantum yield for solid sample was 36.98% and this compound can emit strong green light in the solid state. Graphic abstract One new Tb(III) metal-organic framework was synthesized by a multi-layer diffusion method at room temperature using thiophene-2,5-dicarboxylate as the bridging ligand and investigated by single-crystal structure, UV-Vis absorption, and fluorescent emission.