Super thermally stable Rb-β-Al2O3:Eu blue phosphor for full-spectra lighting

Luminescent thermal stability is an important parameter in evaluating the potential utilization of phosphors. Herein, by manipulating the M in M-β-Al2O3:Eu (M = Na, K, Rb) phosphors, the local environment stability of activators is improved, and the luminescent thermal stability of Rb0.92-β-Al2O3:0.08Eu (Rb-β-Al2O3:Eu) is significantly enhanced to 97%@500 K with high internal/external efficiency (IQE/EQE = 92%/59%). By depositing the commercial green, red, and as-synthesized blue Rb-β-Al2O3:Eu phosphors on a near-ultraviolet (n-UV) chip, a WLED with high correlated rendering index (CRI = 95.1) and low correlated color temperature (CCT = 3963 K) was fabricated. These results prove that Rb-β-Al2O3:Eu is a promising blue phosphor for different lighting scene applications.