CaZrO₃:Tb phosphors synthesis and thermoluminescence characterization after being exposed to beta particle irradiation

Calcium zirconate (CaZrO₃) is a perovskite with orthorhombic structure that possesses remarkable physical properties, such as a high melting point of 2368 °C (Du et al., 1992) and a good thermal shock resistance (Schafföner et al., 2013), These properties coupled with a low phonon frequency make CaZrO₃ a good proposition to host ions possessing interesting luminescent properties (Maurya, 2018), currently there are multiple reports of the photoluminescence (Fl) of CaZrO₃ with different dopants, including rare earths (Ballem, 2017; Khan et al., 2021; Venugopal et al., 2021). Although CaZrO₃ can be synthesized by different methods, the solid-state reaction method is more convenient because of its relative ease, high yield of synthesis in addition to not generating waste. In this work, we report the synthesis of CaZrO₃:Tb phosphors with different molar concentrations of Tb through a solid-state reaction and their thermoluminescence (Tl) characterization using beta radiation as Tl excitation source. The morphological and structural characterizations were carried out by scanning electron microscopy and X-ray diffraction, respectively. The Tl response of the synthesized phosphors with 0.5 mol of terbium showed remarkable reproducibility in successive irradiation – Tl readout cycles, and a glow curve with two maxima located at 135 and 215 °C. The integrated Tl as a function of the irradiation dose exhibits a linear dependence in the dose range from 0.5 up to 32 Gy. The photoluminescence spectrum confirms the inclusion of Tb in the CaZrO₃ lattice. From the experimental evidence here presented, we conclude that the synthesized CaZrO₃:Tb phosphors are promising materials to be used as radiation dosimeters. (author)