Fabrication, Physical, Optical and γ-Ray Absorption Characteristics of Bi³⁺ Ions Doped Borate Barium Fluoride Ytterbium Glasses: Role of the Substitution of B₂O₃/Bi₂O₃ in the Borate Glass System

Bi³⁺ ions doped borate barium fluoride glasses with nominal compositions of (59-x)B₂O₃ + 20BaF₂ + 20Li₂O + 1Yb₂O₃ + xBi₂O₃ with x = 0 (BBLYBi-0), 1 (BBLYBi-1), 3 (BBLYBi-3), 5 (BBLYBi-5), and 7 (BBLYBi-7) mol% have been prepared by using well-known melt quenching method. Borate barium fluoride glasses doped with Bi₂O₃ have been investigated by means of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and UV–Vis measurements. In addition to the MCNP5 simulation code and Phy-X software have been applied in order to evaluate the mass-(MACs) absorption coefficients as γ-ray absorption parameter of the BBLYBi-glasses. The XRD pattern for borate barium fluoride glasses doped with Bi₂O₃ verified the amorphous nature of the samples. The FTIR spectra exhibited many absorption bands with a combination of broad and sharp peaks. The inclusion of Bi³⁺ ions in the suggested glass networks leads to increase the density (ρ) from 3.2443 to 3.6824 g/cm³ and the molar volume (V_m) increases from 26.5254 cm³/mol to 30.9039 cm³/mol. The optical band gap reduced as increasing Bi³⁺ content; the direct optical gap ( \(E_{g}^{Direct}\) $E_g^{\mathit{Direct}}$ ) ranged from 3.98 ± 0.01 to 3.59 ± 0.01 eV, while the indirect optical ( \(E_{g}^{Indirect}\) $E_g^{\mathit{Indirect}}$ ) ranged from 3.47 ± 0.01 to 2.90 ± 0.01 eV. The studied samples exhibited a decreasing in Urbach’s energy, suggesting a decrease in the structural disorder inside the glass samples. The maximum MACs values were 49.491cm²/g, 44.043cm²/g, 37.713 cm²/g, 30.268 cm²/g, and 26.031 cm²/g for BBLYBi-0, BBLYBi-1, BBLYBi-3, BBLYBi-5, and BBLYBi-7 samples, respectively. Results of MCNP5 simulation code and Phy-X software confirm that the MACs of the studied glasses were enhanced as Bi³⁺ increasing in the glass networks. Therefore, the suggested glasses are appropriate for usage in optical and radiation shielding regions.