Effect of Mg substitution on structure and photoluminescence of MgxZn1-xMoO4:Tb3+ phosphor

The compositions in the series MgxZn1-xMoO4:Tb3+ (x = 0.1-0.5) doped with 15 mol% Tb were prepared by the co-precipitation method. Phase impurity, morphology, composition, and formation processes of MgxZn1-xMoO4:Tb3+ phosphors were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and thermogravimetry-differential thermal analysis (TG-DTA). The experimental results show that Mg2+ doping has innegligible effect on the morphology of phosphors. The optimum Mg' concentration is 10 mol% which can obtain uniformly particles with diameters in the range of 1.0-2.0 mu m. In addition, when Mg2+ concentration increases to 30 mol%, MgxZn1-xMoO4:Tb3+ phosphors exhibit satisfactory and excellent green light monitored at 541 nm and their photoluminescence intensity is about 2 times stronger than that of single-doped ZnMoO4:Tb3+ phosphors under the 378 or 488 nm excitation, respectively. (C) 2012 Elsevier B.V. All rights reserved.