Recent research has focused on the fabrication and properties of barium fluoride borosilicate glass samples doped with varying amounts of Gd2O3, underscoring their potential applications for radiation shielding and opto-electronic devices. This innovative study, carried out by researchers from Princess Nourah bint Abdulrahman University, explored the structural, physical, and optical characteristics of these glasses, along with their capacity for γ-ray attenuation.
The investigation utilized the conventional melt quenching technique to manufacture the glass samples (designated as BSBLG0 to BSBLG4) with increasing Gd2O3 substitution ratios. The resulting materials exhibited notable variations in density, ranging from 2.74 to 2.91 g/cm³, and molar volume, which increased from 31.27 cm³/mol to 31.49 cm³/mol as Gd2O3 concentration increased. These alterations are attributed to the molecular weight and density differences between Gd2O3 and B2O3, with Gd2O3 significantly enhancing the density of the glass network.
Various analytical methods were employed to examine the resultant glasses. X-ray diffraction (XRD) analysis confirmed the amorphous nature of the samples, lacking any crystalline peak, which is characteristic of glasses. Meanwhile, the UV-Vis absorption spectra indicated rising absorbance levels within the visible and ultraviolet ranges, signifying the enhanced optical properties due to the Gd2O3 doping.
Critical findings related to the energy gaps of these glasses revealed direct optical gaps ranging from 3.40 eV to 3.21 eV, with indirect gaps decreasing from 2.88 eV to 2.74 eV as the Gd2O3 concentration increased. This trend highlights the influence of non-bridging oxygens and the modification of the glass structure by Gd3+ ions. The study also identified increased values for Urbach’s energy (Eu), illustrating the formation of imperfections within the glass network.
Further, the researchers investigated the glasses' γ-ray attenuation capabilities. Using simulations and physical measurements, they established relationships among the mass attenuation coefficients (MAC), linear attenuation coefficients (LAC), and the effective atomic number (Zeff) of the materials. Results indicated higher MAC values with increased Gd2O3 content across all photon energies tested.
For example, the MAC values at 0.06 MeV for BSBLG0 to BSBLG4 were found to range from 2.824 to 3.443 cm²/g, affirming the enhanced radiation shielding performance attributed to the high atomic number of Gd. The half-value layers (HVL) corresponding to each sample also demonstrated varying thresholds, with BSBLG4 exhibiting the lowest HVL at 0.069 cm at 0.06 MeV, again underscoring its superior shielding potential.
Overall, the findings from this study suggest significant advancements in the development of Gd2O3-doped barium fluoride borosilicate glasses for use not only as effective radiation shielding materials but also as components for opto-electronic devices like solar cells and LEDs. The authors conclude, "The results revealed the suggested glasses can be applied in opto-electronic devices and radiation shielding applications," highlighting the materials' versatility and promising future.
