Gd(III) Coordination Polymer with a 1,2-Connected (2-Nodal) Net for Water-Splitting and Antibiotics Detection

A multifunctional gadolinium-based coordination polymer, [Gd(Cei)(H2O)]n+ (Gd-CP), constructed from bis(2-carboxyethyl) isocyanurate (H2Cei), was synthesized via a hydrothermal strategy and structurally characterized by single-crystal X-ray diffraction. The framework crystallizes in the monoclinic C2/c space group, where eight-coordinated Gd3+ centers adopt a distorted square-antiprismatic geometry to form a robust coordination network. The material exhibits efficient catalytic activity toward water splitting, delivering visible-light-driven hydrogen evolution with a cumulative H2 production of 28.52 mmol g–1 and a rate of 7.13 mmol h–1 g–1, along with promising electrocatalytic activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) with favorable kinetics and good durability. The increasing presence of antibiotic and pharmaceutical residues in aquatic environments necessitates rapid and sensitive monitoring approaches. In this regard, Gd-CP functions as a selective luminescent sensor for riboflavin (RBF) and colchicine (COL), exhibiting strong fluorescence quenching with Stern–Volmer constants of 3.1 × 104 M–1 and low detection limits of 1.430 and 1.158 ppm, respectively. These findings highlight Gd-CP as a versatile platform integrating water-splitting catalysis and pharmaceutical sensing within a single coordination framework.