h-BN modified Mg2Al4Si5O18:Eu2+ phosphor-in-glass film coated on the Lu3Al5O12:Ce3+ transparent ceramic for high color-rendering laser-driven lighting

Garnet transparent ceramics are promising color converters for white laser diodes (LDs) because of their efficient broadband emission and favorable thermal properties. Herein, composite color converters were prepared by integrating the Lu 3 Al 5 O 12 :Ce 3+ (LuAG:Ce) transparent ceramics with h-BN modified Mg 2 Al 4 Si 5 O 18 : Eu 2+ (MAS:Eu) phosphor-in-glass films (PiGFs). Under 450 nm excitation, the LuAG: Ce-BN-MAS:Eu composites exhibit broad emission bands ranging from 480 to 720 nm, and the relative Eu 2+ /Ce 3+ emission intensity ratio rises with increasing h-BN content. The optimized LuAG:Ce-2BN-MAS:3Eu sample shows the highest emission intensity, with an internal quantum efficiency of 92.46% and an external quantum efficiency of 42.83%. In addition, the emission intensity at 150 °C retains 94.56% of that at room temperature. Under blue-laser irradiation at 12.5 W∙mm -2 , the steady-state temperature of light spot remains below 76.7 °C. The constructed laser-driven lighting device exhibits a luminous efficacy of 83.45 lm∙W -1 , a correlated color temperature of 6103 K and a Ra of 85.8. These results indicate that the LuAG:Ce-BN-MAS:Eu composites exhibit great potential for high-color-rendering white LDs.