Photoluminescence and afterglow of deep red emitting SrSc2O4:Eu2+

Abstract

This work deals with the photoluminescence (PL) properties of SrSc₂O₄:Eu²⁺ and SrSc₂O₄: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 SrSc₂O₄: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 SrSc₂O₄:Eu²⁺ and SrSc₂O₄:Eu²⁺,Dy³⁺ was investigated. To this end, PL lifetime measurements were conducted. SrSc₂O₄:Eu²⁺ shows an emission band in the deep red spectral range. Moreover, it turned out that the red emission of SrSc₂O₄:Eu²⁺ shows persistent luminescence too.