Long afterglow yellow luminescence from Pr3+ doped SrSc2O4

A yellow emitting long afterglow luminescence material SrSc2O4:Pr3+ was successfully prepared by solid state reaction method. SrSc2O4:Pr3+ phosphor shows a long afterglow luminescence peak at about 495, 545, 621, 630 and 657 nm, respectively, corresponding to the f–f transitions of Pr3+. The afterglow chromaticity coordinates of SrSc2O4:1 at%Pr3+ were calculated to be (0.35, 0.41), indicating that the afterglow emission is close to the light of yellow region. And, the afterglow luminescence of the optimal sample doped by 1 at%Pr3+ can persist for over 3 h. The thermoluminescence results suggest that there are three types of traps with depth of 0.61, 0.69 and 0.78 eV exiting for all the samples, which are produced by the addition of Pr3+ ions. The trap density of SrSc2O4:1 at%Pr3+ is the maximum when the incorporation of Pr3+ ions reaches 1 at%, which thus results in the longest afterglow luminescence. All the results indicate that SrSc2O4:Pr3+ can be a potential candidate of novel long afterglow phosphors.