Green Synthesis and Characterization of High‐Performance Europium Complex/CaCO 3 Core‐Shell Fluorescent Materials

ABSTRACT In this study, Eu (III) complex/CaCO 3 composite fluorescent materials were prepared by employing CaCO 3 as a substitute for conventional alkaline reagents. The composite materials were comprehensively characterized by means of FT‐IR, XRD, TG‐DTA, SEM, TEM, ICP, EDS, and fluorescence spectroscopy to investigate their structural and performance properties. The results demonstrated that a CaCO 3 ‐core@shell structure was successfully constructed in the composite material. Through this structural configuration, the acid present in the reaction system was effectively neutralized by CaCO 3 , while an environmentally benign preparation process was simultaneously achieved. The fluorescent properties of the composite material were systematically investigated. A maximum absolute quantum yield of 48.39% was measured, representing a 3.39% enhancement compared with the pristine Eu (TTA) 3 Phen complex. Concurrently, the fluorescence lifetime in the composite material was stable at 0.78–0.80 ms due to reduced quenching from the dilution effect of CaCO 3 . Furthermore, when the composite material was implemented in LED devices, warm‐tone red emission was achieved with a fluorescent intensity of 21,970 cd/m 2 being attained. A novel strategy for preparing green and resource‐efficient rare earth complexes was developed in this study. The composite material was demonstrated to possess potential applications in agricultural films, lighting, and display technologies.