3D Cadmium(II)‐Based Coordination Polymer Constructed from V‐Shaped Semirigid Ligand: Selective Detection of Oxoanion Pollutants CrO42–, Cr2O72–, MnO4– in Water

A new coordination polymer (CP), namely, [Cd(HL)(4,4′‐bipy)] (1) (H3L = 4‐(5‐carboxy‐pyridine‐3‐yloxy)‐phthalic acid, 4,4′‐bipy = 4,4′‐bipyridine), was synthesized employing a V‐shaped asymmetric tricarboxylic acid ligand under hydrothermal condition. Single‐crystal X‐ray diffraction analysis indicates that compound 1 exhibits a novel three‐dimensional (3D) framework with (3, 5)‐connected (63)(69·8) topology. Meanwhile, it shows high selectivity and sensitivity for oxoanion pollutants CrO42–, Cr2O72–, and MnO4– anions in aqueous solutions with detection limits of 4.12 × 10–6 M, 1.75 × 10–6 M, and 6.47 × 10–7 M, respectively. The high selectivity and low detection limit indicate that the compound is promising functional luminescence probe for CrO42–, Cr2O72–, and MnO4–. The mechanisms of the quenching effect and sensing properties were discussed in detail.