Luminescence properties of monodispersed spherical BaWO:Eu microphosphors for white light-emitting diodes.

Monodispersed spheres (1-4 μm in diameter) of BaWO:Eu (hereafter BWO:Eu) red-phosphor exhibiting intense emission at 615 nm were synthesized via a mild hydrothermal method. X-ray diffraction, scanning electron microscope, photoluminescence excitation and emission spectra, and decay curve were used to characterize the properties of BWO:Eu phosphors. An intense red emission was obtained by exciting either into the L state with 394 nm or the D state with 465 nm, that correspond to two popular emission lines from near-UV and blue LED chips, respectively. The values of Ω experimental intensity parameters (13.8 × 10 and 8.2 × 10 cm) are determined. The high-emission quantum efficiency of the BWO:Eu phosphor suggests this material could be promising red phosphors for generating white light in phosphor-converted white light-emitting diodes. [ABSTRACT FROM AUTHOR]