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

Applied Physics A (Impact Factor: 1.69). 06/2010; 99(4):859-863. DOI: 10.1007/s00339-010-5614-3

ABSTRACT 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.

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