A stable 3D porous coordination polymer as multi-chemosensor to Cr(iv) anion and Fe(iii) cation and its selective adsorption of malachite green oxalate dye

Abstract

Based on Zn(NO₃)₂·6H₂O and 4,4′-((5-carboxy-1,3-phenylene)bis(oxy))dibenzoic acid (H₃cpbda), a 3D porous coordination polymer, {[Zn_2.5(cpbda)(OH)₂]·solvent₂}_n (solvent = DMF and DMA) (1), was synthesized by three solvent-thermal methods. The complex was characterized by single-crystal X-ray diffraction, IR spectroscopy, power X-ray diffraction, thermal-gravimetric analysis and fluorescence spectroscopy. Owing to its good thermal stability and fluorescence, the sensing experiments (eighteen kinds of cations and eleven kinds of anions) and the further titration processes show the complex can sensitively detect the Fe(III) metal cation and Cr(VI) anions (Cr₂O₇²⁻ and CrO₄²⁻) by the quenching responses. In addition, further adsorption research of seven dyes shows the complex 1 can selectively adsorb the Malachite Green Oxalate (MGO) dye.