Optical behavior and TL kinetics of Eu³⁺ and Tb³⁺ doped zirconate thermoluminescent phosphors

The influence of Tb³⁺ and Eu³⁺ ions on the optical behavior and TL kinetics of the synthesized phosphors were analyzed here. The AZrO₃ (A = Ca, Ba, Sr) phosphors activated with Eu³⁺ and Tb³⁺ ions were prepared using solid state reaction technique. The doping concentration of Eu³⁺ and Tb³⁺ ions is varied from 0 to 2 mol% for each. The PXRD analysis is done to study various crystallographic aspects of synthesized phosphors. It confirms the crystalline structure, phase purity and homogeneity of synthesized phosphors. The FESEM and TEM analyses show formation of particles with irregular shape and variable dimensions. The agglomeration of these particles is a resultant of prolonged heat treatments involved in solid state reaction method at elevated temperatures. The study of TL spectra of UV and gamma irradiated phosphors set forth their second order kinetics. The electrons were trapped in trap centers with high trap depth and hence high amount of energy (~ 3 eV) is required to vacate them. The doping of trivalent rare earth impurity ions in the perovskite host lattice leads to formation of these traps centers. With enhanced TL intensity and low fading characteristics, these phosphors are suitable alternatives for TL mapping and sensing applications.