Crystal Structure and Luminescent Properties of Eu2+-Doped Li2BaSiO4 with a Polymorph for White LEDs

The crystal structure and photoluminescence of Li2BaSiO4:Eu2+ phosphors were investigated. A preliminary conclusion was reached through X-ray diffraction, Fourier transform infrared absorption, photoluminescent excitation and emission investigations that a Li2BaSiO4 polymorph was found. The Li2BaSiO4:Eu2+ characterizes an intense blue emission with a peak at 465 nm and a broad excitation band in the UV/visible range. Warm white light with CIE coordinates (0.334, 0.347) and color temperature of about 5500 K is generated by mixing this blue phosphor with the Li2SrSiO4:Eu2+ yellow phosphor. These results indicate that Li2BaSiO4:Eu2+ with the polymorph of the host would be a promising blue phosphor candidate for UV-chip-based multiphosphor converted white light-emitting diodes (LEDs).