A Novel Blue-Emitting Phosphor NaBaPO4:Eu2+ for White LEDs

A novel blue phosphor based on phosphate host matrix, NaBaPO4 doped with Eu was prepared by solid state reaction. The phosphor invariably emits blue luminescence with a peak wavelength at 440 nm under ultraviolet excitation. The excitation spectrum is very broad extending from 300 to 450 nm, which is coupled well with the emission of UV LED (350-410 nm). The effect of doped Eu concentration on the emission intensity of NaBaPO4:Eu phosphor was also investigated and the process of energy transfer between Eu ions in NaBaPO4 phosphor should be controlled by multipole interaction. The measured of InGaN-based NaBaPO4:Eu LED shows bright blue light to the naked eye with chromatic coordinate of (0.1632, 0.1098). Keywordswhite LEDs; phosphor; Eu2+