Well-Performed Green Phosphor BaY4Si5O17:Ce3+,Tb3+ with High Quantum Efficiency and Thermal Stability

Abstract

For Tb³⁺-doped green phosphors, the energy transfer from Ce³⁺ to Tb³⁺ can largely enhance the absorption of excitation; however, obtaining phosphors that exhibit both high quantum efficiency and thermal stability continues to pose a significant challenge. Herein, we established a paradigm to achieve novel silicate BaY₄Si₅O₁₇ (BYSO):Ce³⁺,Tb³⁺. The near-ultraviolet light efficiently excites the BYSO:Ce³⁺ material, causing it to emit light at a wavelength of 408 nm. The photoluminescence of BYSO:0.12Ce³⁺ exhibits a relatively small Stokes shift and a thermal stability of 89.8% of the 303 K emission intensity at 423 K (89.8%@423 K). The energy transfer (ET) from Ce³⁺ to Tb³⁺ ions can be readily constructed in BYSO:Ce³⁺,Tb³⁺ utilizing the overlap between the Ce³⁺ emission and the Tb³⁺ excitation. The ET efficiency from the Ce³⁺ to Tb³⁺ ions reached 83.8% at y = 1.2 and a maximum of 94.6%. Finally, the optimized phosphor BYSO:0.12Ce³⁺,1.2Tb³⁺ had an internal quantum efficiency of 94.4% and had excellent thermal stability (96.1%@423 K). Our work pointed out the avenue to novel green phosphors with high efficiency and thermal stability by choosing appropriate host and construct efficient ET.