The luminescence properties of Eu2+ doped Na2CaMg(PO4)2 phosphor

The blue-emitting phosphors of Eu2+-doped Na2CaMg(PO4)2 were prepared by high-temperature solid-state reaction. The crystal phase formation was confirmed by X-ray powder diffraction measurement. The luminescence properties were investigated by photoluminescence excitation and emission spectra. The phosphor exhibited the blue luminescence due to the 4f65d1→4f7 transition of Eu2+ ions under the excitation of near UV light. The influence of temperature on the luminescence intensities and decay lifetimes of Eu2+ was investigated. An unusual increase of the decay lifetimes of the 4f65d emission of Eu2+ ion is observed in Na2CaMg(PO4)2 from 10 K to room temperature. The thermal stability of the luminescence of Eu2+-doped Na2CaMg(PO4)2 was discussed.