Green long-after-glow luminescence of Tb³⁺ in Sr₂SiO₄

The green long-after-glow luminescence from Tb³⁺-doped Sr₂SiO₄ phosphors, which are synthesized by the high temperature solid state reaction in a reductive atmosphere, is observed in this paper. The results show that under ultraviolet excitation, the obtained phosphors produce an intense green-lighting-emission from the Tb³⁺, and the green-lighting long-after-glow luminescence related to Tb³⁺ can last half an hour after the irradiation source has been removed. Moreover, the effects of co-doping Li⁺, Dy³⁺, Er³⁺, Gd³⁺, and Yb³⁺ with Tb³⁺ on the decay properties and thermoluminescence properties are investigated to confirm the long-after-glow mechanism.