Eu3+在La2O2S中的长余辉发光

The new Eu 3+ doped lanthanum oxysulfide phosphors,which have the orange-red long afterg low emission,were synthesized by solid-state reaction method.The synthesized phosphors were characterized by X-ray diffraction.The excitation and emission spectra,afterglow spectra and afterglow decay curves were examined.XRD confirm ed the phosphor as pure phase La 2 O 2 S.The phosphors showed typical transitions 5 D J (J=0,1) → 7 F J (J=0,1,2,3,4)of Eu 3+ .The photoluminescence spectra and afterglow spectra presented the regular alteration with various Eu 3+ concentration,due to cross relaxation between energy levels of Eu 3+ .In addition,we studied the effects of activator concentration and dopants species on the afterglow property.The data showed afterglow result was the bes t with2%Eu 3+ and doped with Mg 2+ and Zr 4+ .A prominent phosphorescence can be seen in this phosphor after illuminated with UV light.