Luminescent properties of Eu 3+ -doped BaZrO 3 phosphor for UV white light emitting diode
摘要
A novel yellowish green phosphor Tb3+ doped calcium molybdate (CaMoO4) was synthesized at 800 ℃ by conventional solid state reaction method and their crystal structure and luminescent properties were investigated. The X-ray diffraction patterns (XRD) showed that they were simple crystalloid of CaMoO4∶Tb3+. Monitored at 550 nm, the excitation spectrum consisted of two bands and the two excitation peaks located at 305 and 380 nm respectively. The emission spectrum excited by 380 nm UV light was composed of four narrow bands. The strongest emission was located at 540 nm corresponding to 5D4-7F5 transition. The appropriate concentration of Tb3+ was 5%(mole fraction) for the highest emission intensity at 550 nm. These results showed that this Tb3+-activated CaMoO4 was a promising yellowish green phosphor for near-ultraviolet (NUV) InGaN-based white LED.