Luminescence studies of MgSO₄:Dy phosphors

Abstract

The lyoluminescence (LL) in MgSO₄:Dy phosphors has been studied. Thermoluminescence (TL) and photoluminescence (PL) have also been studied to understand the mechanism of LL. MgSO₄ phosphors containing different concentrations of Dy (0.05-1.0 mole%) have been prepared by solid-state diffusion method. The maximum LL intensity is observed for 0.05 mole% of Dy in MgSO₄. TL glow curves of MgSO₄:Dy phosphors are complex and peaks around 110, 150 and 220ºC are observed. The effect of post-irradiation annealing on the LL shows that with removal of 220ºC TL peak, the LL intensity decreases markedly. LL and TL intensity of MgSO₄:Dy phosphors have also been recorded for different g-doses. PL studies conducted on the sample show that Dy³⁺ ion acts as the luminescence center in MgSO₄ phosphor.