Modulation and Enhancement of Red Luminescence in Ca 2 GdSbO 6 : Eu 3+ Phosphor by Co-Doping with Bi 3 .

The double perovskite structure of Ca ₂ GdSbO ₆ as a fluorescent phosphor matrix material possesses a stable structure, making it an excellent candidate for a matrix material. In this study, single-doped Ca ₂ GdSbO ₆ : Eu ³⁺ fluorescent phosphors and Bi ³⁺ sensitized Ca ₂ GdSbO ₆ : Eu ³⁺ , Bi ³⁺ fluorescent phosphor materials were synthesized using the high-temperature solid-state method. The luminescence of this phosphor is based on the ⁵ D ₀ → ⁴ F ₂ transition emission of Eu ³⁺ ions, which occurs at 612 nm. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) spectra, high-temperature fluorescence spectra, and fluorescence decay lifetimes to study the phase structure, optical properties, crystal structure, and chemical purity of the samples. The performance of the single-doped phosphor was significantly improved by the addition of Bi ³⁺ sensitizer. The luminescence intensity increased by nearly 100% compared to Ca ₂ GdSbO ₆ : Eu ³⁺ phosphor, with a quantum efficiency increase of 124%. The thermal quenching activation energy was found to be 0.299 eV, and the luminescence intensity remained at 70.3% of room temperature at 453 K. These results indicate that the co-doping of Bi ³⁺ has a modulation and enhancement effect on the luminescence of Ca ₂ GdSbO ₆ : Eu ³⁺ red phosphor, showing great potential for application in near-ultraviolet-excited white LED devices.
(© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)