Highly enhanced luminescence of GdTaO4:Eu3+ phosphors by codoping with Zn2+ ions

GdTaO4:Eu0.1Znx phosphors were synthesized by the conventional solid-state reaction. The effects of Zn2+ ions on the crystallization behavior, morphology and photoluminescence (PL) properties of GdTaO4:Eu3+ were investigated. The results indicate that the PL intensity of GdTaO4:Eu3+ phosphor was improved remarkably by Zn2+ doping. There were two maxima in PL intensity against Zn2+ dopant concentration, one was improved up to 2.7 times at x = 0.01 and the other was enhanced up to 3.2 times at x = 0.13. The first maximum was regarded as the incorporation of Zn2+ ions altering the local environment of activator Eu3+ ions and the second maximum was due to the flux effect of Zn2+ ions. And the phases of ZnO and GdTa7O19 were observed in excessive Zn2+ doping range (x > 0.13). The considerably enhanced PL brightness and shorten luminescent lifetime of Zn-doped GdTaO4:Eu3 is very encouraging for the display applications.