Simultaneous adsorption and fluorescent detection of Cr(VI) via lanthanide coordinating polymeric porous microparticles

Abstract

Functional porous microparticles that enable simultaneous adsorption removal and online monitoring of hazardous hexavalent chromium are of great importance for effective remediation of Cr(VI) pollution. Herein, we have synthesized, for the first time, an oligomer bearing aromatic backbone and pendent carboxyl, sulfonate as well as amidoxime groups, which has been further employed as the dual functional ligand to coordinate with lanthanide ions of Tb3+ via a facile one-step solvent exchange induced self-assembling, leading to generation of the cube-like fluorescent porous microparticles. Thanks to their porous structure, abundant surface binding sites as well as green fluorescence emission that can be selectively quenched by Cr(VI), the obtained lanthanide coordinated polymeric porous microparticles exhibited both competitive adsorption and fluorescent detection of Cr(VI). More specifically, the optimized fluorescent porous microparticles demonstrated a maximum Cr(VI) adsorption capacity of 553.92 mg·g−1 and a limit of detection for Cr(VI) down to 1.92 nM according to systematic adsorption and detection experiments. On account of scalable synthesis of oligomer ligand, facile preparation of microparticles as well as their competitive dual adsorption and detection of Cr(VI), the current work basically opens new way for design and fabrication of advanced materials for heavy metal ions pollution controls.