A novel Dy3+activated Ba4La6O(SiO4)6 phosphor with robust thermal stability for WLED applications

With the ongoing advancements of phosphor- converted white light emitting diodes (pc-WLEDs), single-phase white-light-emitting phosphors characterized by their efficient properties and stable luminescence have emerged as an effective strategy to solve the limitations of existing lighting technologies. In this study, a series of Ba4La6O(SiO4)6: Dy3+ (BLSO: Dy3+) phosphor was synthesized, which, under 349 nm light excitation, exhibits characteristic blue and yellow emissions of Dy3+ within the ranges of 465-505 nm and 555-605 nm, respectively, corresponding to the 4F9/2 -> 6H15/2 and 6H13/2 transition processes. The maximum emission intensity is achieved when the Dy3+ doping concentration is 0.14. Above this concentration, the observed concentration quenching can be attributed to electric dipole-electric dipole interactions. Notably, the luminescent intensity at 423 K remains 97.6 % of that at room temperature. Herein, the luminescent properties are further enhanced upon the introduction of Sr2+, accompanied by an improvement in thermal stability, achieving a negative thermal quenching capability of 103 % at 423 K, with the emission color shifting towards white light. The co-doping of Ce3+ enhances the blue emission component, realizing the better white light emission with color coordinates of (0.32,0.33). This study conclusively demonstrates this phosphor exhibit tremendous potential in the field of solid-state white lighting applications.