NOVEL BLUE-EMITTING KSrBP₂O₈: Eu²⁺ PHOSPHOR FOR NEAR-UV LIGHT-EMITTING DIODES

A blue-emitting borophosphate KSrBP₂O₈: Eu²⁺ is synthesized and evaluated as a candidate for near ultraviolet white light emitting diodes. This phosphor shows strong excitation band in 250~420 nm, and a broad and asymmetry emission band with a tail on the long-wavelength side. According to investigating on the crystal structure, the asymmetry emission band results from the certain degree of substitutional disorder of Eu ²⁺ in KSrBP₂O₈: Eu²⁺ . The emission intensity of the optimal sample with 5% Eu ²⁺ is reached to 89% of that of the commercial BaMgAl₁₀O₁₇: Eu²⁺ under excitation at 365 nm, and the quantum efficiency of the optimal sample is 48.9%. The results reveal that the potential application of KSrBP₂O₈: 5% Eu²⁺ as a blue-emitting UV convertible phosphor for white light emitting diodes is feasible.