Solid state synthesis and luminescence of NaLa(WO4)2:Dy3+ phosphors

A series of Dy3+ doped NaLa(WO4)(2) phosphors have been synthesized by a solid state reaction. The phase and luminescence of these obtained phosphors are studied. All of Dy3+ doped NaLa(WO4)(2) phosphors have the XRD patterns similar to pure NaLa(WO4)(2) with tetragonal scheelite structure, suggesting that the Dy3+ doping in NaLa(WO4)(2) will not change its phase structure. The Dy3+ doping concentrations have obvious influence on the luminescent properties of NaLa(WO4)(2):Dy3+ phosphors. Under the excitation at 351 nm, NaLa(WO4)(2):Dy3+ phosphors show emission bands originating from F-4(9/2) -> H-6(15/2), F-4(9/2) -> H-6(13/2) and F-4(9/2) -> H-6(11/2) transitions of Dy3+ ions. The emission spectra of NaLa(WO4)(2):Dy3+ phosphors show that the critical concentration of Dy3+ in NaLa(WO4)(2) is about 0.08 mol. The CIE coordinates show that the colors of NaLa(WO4)(2):Dy3+ phosphors change in the near yellow-white region.