Afterglow improvement of high concentration Dy<sup>3+</sup> co-doped SrAl<sub>2</sub>O<sub>4</sub>:Eu<sup>2+</sup> phosphor prepared by H<sub>3</sub>BO<sub>3</sub> free synthesis using melt quenching method

Melt quenching method was applied to prepare the long persistent phosphor SrAl2O4:Eu2+,Dy3+, and Dy3+ concentration dependence of afterglow property was investigated. Melt quenched SrAl2O4:Eu2+,Dy3+ phosphors exhibit brighter afterglow intensity compared with these synthesized by a conventional solid-state reaction method. The afterglow property was improved with increase of Dy3+ concentration, and 10 mol % Dy3+ co-doped sample exhibits approximately 1.3 times higher afterglow intensity than commercially available phosphor.