High-efficiency cubic-phased blue-emitting BaLuBO:Ce phosphors for ultraviolet-excited white-light-emitting diodes.

In this work, Ce-activated BaLuBO (BLBO) blue-emitting phosphors were prepared, and their photoluminescence properties were studied. It was found that these phosphors can be excited over a broad excitation band range from 300 nm to 430 nm and generated a blue emission band in the 400-550 nm range with a maximum peak at 443 nm. The full width at half maximum of the blue emission band was about 68 nm. The optimal doping concentration of Ce ions was determined to be 3 mol. %, and the BLBO:0.03Ce phosphors possessed an internal quantum efficiency as high as 71%. Finally, by coating the phosphors with a blend of commercial CaAlSiN:Eu red-emitting phosphors, (Ba,Sr)SiO:Eu green-emitting phosphors, and BLBO:0.03Ce blue-emitting phosphors on a 380 nm ultraviolet light-emitting diode (LED) chip, a white LED device with a color-rendering index of ∼94 and correlated color temperature of 4952 K was obtained.