Carboxyl-functionalized poly(arylene ether sulfone)-terbium(III) coordination polymer-based fluorescent fibrous membrane for highly sensitive detection of Cr(VI) ions

Abstract

Hexavalent chromium (Cr(VI)), a widely utilized yet highly toxic industrial heavy metal, frequently contaminants industrial wastewater, thereby posing significant risks to ecosystems and human health. Therefore, the development of a rapid and highly sensitive method for detecting Cr(VI) is crucial. In this study, we constructed a novel fluorescent fibrous membrane by utilizing carboxyl-functionalized poly(arylene ether sulfone) (CPES) as a polymer ligand to form Tb(III) coordination polymers. The resulting fibrous membrane emits intense green fluorescence under ultraviolet light and exhibits excellent fluorescence stability across a broad range of NaCl concentrations (0 - 1.0 M) and pH values (1 - 14), attributable to the inherent chemical robustness of the CPES backbone. The presence of Cr(VI) induces significant fluorescence quenching of the membrane, achieving a detection limit of 8.6 μM in aqueous solution. Importantly, the membrane demonstrates remarkable reusability, with no significant decrease in fluorescence intensity even after eight consecutive detection-regeneration cycles. In summary, the CPES-Tb(III) fibrous membrane combines high selectivity, sensitivity, anti-interference capability, and reusability, marking it a highly promising material for detecting Cr(VI) in industrial wastewater and providing a solid foundation for the development of next-generation portable sensors.