TSL, OSL and ESR studies in ZnAl2O4:Tb phosphor

ZnAl₂O₄:Tb phosphor was prepared by combustion synthesis. ZnAl₂O₄:Tb exhibits three thermally stimulated luminescence (TSL) peaks around 150, 275 and 350 °C. ZnAl₂O₄:Tb exhibits optically stimulated luminescence (OSL) when stimulated with 470 nm light.Electron spin resonance (ESR) studies were carried out to identify defect centres responsible for TSL peaks observed in ZnAl₂O₄:Tb. Two defect centres are identified in irradiated ZnAl₂O₄:Tb phosphor and these centres are assigned to V and F⁺ centres. V centre appears to correlate with the 150 °C TSL peak, while F⁺ centre could not be associated with the observed TSL peaks.