Thermoluminescent behavior of UV and γ rays irradiated Eu2+ and Er3+doped silicate phosphors

Abstract

Abstract This paper reports the structural, morphological and thermoluminescent studies of Eu2+ and Er3+ ions activated ASiO3 (A = Ca, Ba, Sr) phosphors synthesized via conventional solid state reaction method. The impurity ions concentration of both Eu2+ and Er3+ ions varies from 0 mol% to 1 mol%. The study of crystallographic traits of the synthesized phosphors is done by Powder X-Ray Diffraction (PXRD) analysis. The crystalline nature, phase purity and appreciable homogeneity of the synthesized phosphors were confirmed by this study. The distinct morphological and topographical features were studied through Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). The thermoluminescent (TL) behavior of ultraviolet (UV) irradiated and gamma irradiated ASiO3:Eu2+, Er3+ (A = Ca, Ba, Sr) phosphors were studied here and the various kinetic parameters were estimated by Computerised glow curve deconvolution (CGCD) technique and peak shape method. The UV and gamma irradiated phosphors exhibit second order kinetics. The high values of activation energy (∼3 eV) confirm the trapping of electrons in deep trap centers. The incorporation of doping ions into the host lattice causes non-valence substitutions at the substitutional sites. This increases the number of defects and vacancies in the phosphors and more trap centers were generated. The increased TL intensity and high temperature glow peaks confirm the same. The synthesized phosphors show enhanced TL characteristics, efficient trapping mechanism and low fading effects. These characteristics confirm the suitability of the synthesized phosphors for TL mapping and sensing applications.