Beta-irradiated ZnGa2O4:Sm3+ phosphor: Thermoluminescence glow curves and kinetic parameters via gel combustion synthesis

This study examines the X-ray Diffraction (XRD) characteristics of Sm ³⁺-doped ZnGa ₂O ₄ phosphor, shedding light on its structural characteristics. The XRD data reveal distinctive peaks that represent the crystal`s lattice structure. This provides the basis for a more detailed analysis of thermoluminescence (TL). Initially, the TL glow curves corresponding to different concentrations of Sm were analysed, leading to the identification of the most favorable Sm concentration. Subsequently, an investigation was conducted into the TL behavior of the material in response to varying doses within a broad spectrum of beta radiation, revealing a linear characteristic (b=1.075) across doses ranging from 0.1 Gy to 50 Gy. Following this, a reusability assessment was executed over three measurement sets, wherein it was ascertained that the deviation in peak area across ten cycles did not surpass 2 %. Furthermore, it was investigated how different heating rates ranging from 0.5 °C/s to 7 °C/s affect the TL curve of the material. To determine the TL trap parameters of the sample, Initial Rise (IR) and Computerized Glow Curve Deconvolution (CGCD) methods were employed. A consistent pattern of activation energy values was observed in both IR in the T <sub>M</sub>-T <sub>stop</sub> experiment and CGCD analyses, indicating a uniform response to distinct energy levels within the sample. In terms of providing valuable insights into the characteristics of TL, these methods were found to be very effective. This contributed to a comprehensive understanding of charge carrier dynamics within the crystal lattice. Moreover, Peaks I, II, and III showed a linear response to applied doses, indicating the material`s potential for dosimetry applications. The findings of this study not only provide insights into Sm ³⁺-doped ZnGd ₂O ₄ phosphors` TL properties, but also enhance our understanding of how to optimize their radiation response.