A novel green-emitting phosphor NaCaPO4:Eu2+ for white LEDs

A novel green-emitting phosphor NaCaPO4:Eu2+ was prepared by high temperature solid state reaction and an efficient green emission under near-ultraviolet was observed. The emission spectrum shows a single intense band centered at 505 nm, which corresponds to the 4f65d1 → 4f7 transition of Eu2+. The excitation spectrum is a broad band extending from 250 to 450 nm, which matches the emission of ultraviolet light-emitting diodes (UV LEDs). The effect of doped Eu2+ concentration on the emission intensity of NaCaPO4:Eu2+ was also investigated. The NaCaPO4:Eu2+ is a potential green-emitting phosphor for white LEDs.