Dy3+/Eu3+ co-doped CsGd(MoO4)2 phosphor with tunable photoluminescence properties for near-UV WLEDs applications

Abstract

A series of color tunable Dy3+/Eu3+ co-doped CsGd(MoO4)2(CGM) phosphors were prepared by the conventional solid state reaction. The crystal structure, morphology, vibrational modes, luminescence properties and energy transfer mechanism were investigated. Upon near ultraviolet (n-UV) excitation, Dy3+/Eu3+ co-doped phosphors exhibit the characteristics blue (4F9/2 → 6H15/2), yellow (4F9/2 → 6H13/2) and red (5D0→7F2) emission corresponding to transitions of Dy3+and Eu3+ions. By changing the doping concentration of Dy3+ and Eu3+, the emission hue could be controlled via the energy transfer mechanism. The energy transfer efficiency and critical distance of Dy3+ and Eu3+ have been calculated. The calculated chromaticity coordinates and color correlated temperature of co-doped phosphors lie at the F4 warm white points of standard illuminants.