An efficient blue-emitting phosphor : for white LEDs

A new blue-emitting phosphor LiCaPO4: Eu2+ was synthesized by solid state reaction at a relatively low temperature of 900 °C. It gives a single intense emission band centering at 470 nm, which corresponds to the 4f65d1→4f7 transition of Eu2+. The dependence of luminescence intensities on Eu2+ concentration was investigated. The phosphor, with a single excitation band extending from 250 to 400 nm, could be efficiently excited by near-ultraviolet light-emitting diodes and is believed to be a promising blue-emitting phosphor for white light-emitting diodes.