KBaScSi3O9:Eu2+ Glass-Ceramics as Single-Phase High-Power White Emitters

Single-phase white-light emitters in the lighting technology overcome the challenges of re-absorption and color shift. However, achieving the broadband white emission in single-phase phosphor remains a challenge. Here, crystallized KBaScSi 3 O 9 :Eu 2+ (KBSSO:Eu 2+ ) glass-ceramics (GC) with abundant cationic sites have been developed and an ultra-broad emission band ranging from 460 to 800 nm have been found, in which the asymmetric green emission is ascribed to the Eu 2+ ions in [KO 8 ] and [BaO 7 ] polyhedra, while the red emission centered at 620 nm is originated from Eu 2+ ions in [ScO 6 ] sites. The optimized GC-converted white LED (WLED) exhibits a high color rendering index ( R a = 89.8) and low correlated color temperature (CCT = 4241 K). Moreover, the encapsulant-free GCc-WLED can operate continuously under high drive currents. This work paves the way for the design and future development of single-phase high-power white light sources.