BaYBO based phosphor ceramic plates with excellent thermal stability for wLED applications.

A series of Eu3+ and Tb3+ singly doped Ba3YB3O9 phosphors were synthesized by a solution combustion approach. The most luminescent phosphors were selected as the starting materials to fabricate phosphor ceramic plates (PCPs). More intense red and green emission is observed from the PCPs than the corresponding phosphors. The emission colour can be effectively tuned by varying the mass ratio of the red and green phosphors and the excitation wavelength. White light emission was obtained by incorporating the blue-emitting Eu2+ doped BaMgAl10O17 phosphor into the PCP component. The synthesized phosphors and PCPs show robust thermal stability, maintaining more than 80% of emission intensity at 423 K of that at 298 K after a long time operation. The results indicate that the prepared red and green PCPs are promising candidates for high-power wLED applications.