Novel bismuth activated blue-emitting phosphor Ba2Y5B5O17:Bi3+ with strong NUV excitation for WLEDs

Abstract

In this work, a series of novel non-rare-earth ion activated phosphors Ba₂Y_5−xB₅O₁₇:xBi³⁺ for white light-emitting diodes (WLEDs) was prepared via the high temperature solid state reaction route. The Ba₂Y_5−xB₅O₁₇:xBi³⁺ phosphors show a tunable emission range from blue to green upon different excitation wavelengths, arising from the intricate energy transfer among multi Bi³⁺ emission centers. Among them, when used as a blue-emitting phosphor, Ba₂Y₅B₅O₁₇:Bi³⁺ has efficient absorption in the range of 360–390 nm, which matches well with the near ultraviolet (NUV) light emitting diode (LED) chips. Furthermore, Ba₂Y₅B₅O₁₇:Bi³⁺ phosphor exhibits good resistance to thermal degradation with a quantum efficiency (QE) of 46% under 370 nm excitation. All results indicate that the Ba₂Y₅B₅O₁₇:Bi³⁺ phosphor has potential application in WLEDs.