High thermal stability and quantum efficiency of (Sr,Ba)2Ga2SiO7: Eu2+ phosphors for full-spectrum WLEDs

High-quality phosphors with color tunability are urgently needed for the full-spectrum white light-emitting diodes (WLEDs) with healthy and comfortable lighting like the solar spectrum. Here, a Sr2Ga2SiO7: Eu2+ phosphor with tunable luminescence color is reported, achieving a luminescence tuning from maize-yellow to yellow by changing the Eu2+ ion concentration. Importantly, the quantum efficiency of BaSrGa2SiO7: 1.0 % Eu2+ is as high as 85.7 % compared with 49.1 % of Sr2Ga2SiO7: 5.0%Eu2+, and the emission intensity of BaSrGa2SiO7: 1.0 % Eu2+ retains 92 % of the room temperature (RT) emission intensity at 473 K by Ba2+ substitution. Furthermore, the increase of Ba2+ ion concentration also makes the phosphor achieve tunability from yellow to green. The as-prepared full-spectrum WLEDs exhibits a continuity spectrum like solar spectrum with an extremely high color rendering index of 93.5 and low correlated color temperature of 4562 K. This work provides new insights into the exploration of new phosphors for high-performance full-spectrum WLEDs devices.