Photoluminescence and afterglow of deep red emitting SrSc2O4:Eu2+

This work deals with the photoluminescence (PL) properties of SrSc2O4:Eu2+ and SrS2O4:Eu2+, Dy3+. For this purpose a series of powder samples of SrSc2O4 with various concentrations of Eu2+ and Dy3+ was prepared. The samples were synthesised via a high temperature solid state route. Phase purity was investigated by conducting X-ray powder diffractometry. The PL properties of all prepared samples were elucidated by recording PL and PL excitation spectra. Furthermore, the temperature behaviour of the PL of SrS2O4:Eu2+ was investigated from 100 to 500 K. Diffuse reflectance spectra were recorded to investigate the optical properties of Eu2+ doped SrSc2O4. Additionally, persistent luminescence of SrS2O4:Eu2+ and SrS2O4:Eu2+, Dy3+ was investigated. To this end, PL lifetime measurements were conducted. SrS2O4:Eu2+ shows an emission band in the deep red spectral range. Moreover, it turned out that the red emission of SrS2O4:Eu2+ shows persistent luminescence too.