Luminescence, energy transfer and color perception studies of Na3Gd(PO4)2:Dy3+:Tm3+ phosphors

Abstract

The white-light-emitting Na3Gd(PO4)2:Dy3+:Tm3+ phosphors were prepared by high temperature solid-state reaction technique. X-ray diffraction, luminescence excitation, emission, and decay measurements were performed. Upon Gd3+8S7/2→6IJ (275nm) excitation, the phosphors emit intense blue and yellow luminescence originating from the Dy3+4F9/2→6H15/2 and Dy3+4F9/2→6H13/2 transitions together with the Gd3+6P7/2→8S7/2 transition at 313nm. The excitation of Tm3+ ions by 352nm radiation results also in efficient yellow and blue luminescence. The luminescence enhancement of Dy3+ in the presence of Tm3+ is discussed. The energy transfer process of the Tm3+–Dy3+ system is also explored. This study includes the color perception analysis of synthesized phosphors. The pure white-light is observed with Na3Gd(PO4)2:1%Dy3+:1%Tm3+ and is a promising material for white-lighting applications.