Impact of Bi 3+ , Ba 2+ , and Pb 2+ ions on the structural, thermal, mechanical, optical, and gamma ray shielding performance of borosilicate glass

A host network of borosilicate glass was produced and reinforced with Bi 3+ , Ba 2+ , and Pb 2+ ions to be used as protective materials against gamma rays. Four glasses, host 70B 2 O 3 –30SiO 2 (BSi), 40B 2 O 3 –30SiO 2 –30Bi 2 O 3 (BSiBi), 40B 2 O 3 –30SiO 2 –30BaO (BSiBa), and 40B 2 O 3 –30SiO 2 –30Pb 3 O 4 (BSiPb), were produced. A perfect amorphous structure was observed in X-ray diffraction patterns for all the considered glasses. The structural results showed that BSiBi glass was enriched by non-bridging oxygens NBO units, while BSiBa and BSiPb glasses were enriched by bridging oxygens BO, leading to more tightness of BSiBa and BSiPb glasses than BSiBi. The structural changes clearly reflected on the thermal and optical properties of the considered glasses, where a clear agreement between the network crowding by NBO or BO units and the behavior of the glass transition temperature, band gap, Urbach energy, and refractive index was observed. The considered BSiBi, BSiBa, and BSiPb glasses had thermal stability of 177.931, 264.634, and 231.036 °C and refractive indices of 2.292, 2.225, and 2.175, respectively. From the elasticity point of view and based on the structural changes, the elastic moduli of the BSiBa and BSiPb glasses were consistent with the tightness and formation of BO units, while those of the BSiBi glass were the opposite of what was expected. Bi 3+ , Ba 2+ , and Pb 2+ enhanced the elastic moduli of the host glass by 70.648–88.042, 119.470–133.114, and 191.773–217.856%. All the considered glasses have high transparency (> 74%). Reinforcing the host glass with Bi 3+ , Ba 2+ , and Pb 2+ significantly improved its attenuation of 661.64, 1173.23, and 1332.51 keV gamma ray energies. It was found that the BSiBi glass is the best attenuator, followed by BSiPb, but with a very high affinity, while the BSiBa is the least attenuator. For the used gamma rays 661.64, 1173.23, and 1332.51 keV, Bi 3+ improved the attenuation ability by 126.087, 134.546, and 115.888%; Ba 2+ improved it by 57.764, 69.091, and 63.551%; and Pb 2+ by 118.012, 110.909, and 107.477%, respectively. Hence, the suitable thermal, mechanical, optical, and attenuation properties of the BSiBi, BSiBa, and BSiPb glasses open up prospects for them as radiation shields in nuclear fields such as immobilization & disposal of radioactive wastes, radiotherapy rooms, and hot cells.