Cadmium(ii) coordination polymers based on 2-(4-((E)-2-(pyridine-2-yl)vinyl)styryl)pyridine and dicarboxylate ligands as fluorescent sensors for TNP

Abstract

Three Cd(II) coordination polymers [Cd(L)(p-BDC)] (1), [Cd(L)(m-BDC)] (2) and [Cd(L)(m-BDC-CH₃)(H₂O)] (3) are synthesized by introducing three carboxylic acids as auxiliary ligands to react with the ligand L and cadmium nitrate (L = 2-(4-((E)-2-(pyridine-2-yl)vinyl)styryl)pyridine, p-H₂BDC = 1,4-benzenedicarboxylic acid, m-H₂BDC = 1,3-benzenedicarboxylic acid, and m-H₂BDC-CH₃ = 5-methyl-1,3-benzenedicarboxylic acid). These complexes have different structures and fluorescence properties despite subtle changes in the ancillary ligands. All the coordination polymers can function as chemical sensors for sensing 2,4,6-trinitropheol (TNP) with high selectivity and sensitivity via the fluorescence quenching effect even in the presence of interfering substances. Furthermore, the complexes are stable enough to be recycled for detection at least five times.