Investigation of $\gamma$ ray shielding, structural and dissolution rate studies of alkali based bismuth borate glass systems with MoO${}_3$ added

Bi${}_2$O${}_3$-B${}_2$O${}_3$-Li${}_2$O-K${}_2$O-MoO${}_3$ glass system has been synthesized using melt-quenching technique. $\gamma$ ray shielding properties have been evaluated in terms of mass attenuation coefficient at photon energies 356, 662 and 1173 keV. These shielding parameters are also compared with standard nuclear radiation shielding material "barite concrete" at the same photon energies. Most of our prepared samples show better $\gamma$ ray shielding properties as compared to barite concrete at the same photon energies. Density, molar volume, XRD, FTIR and Raman studies have been employed to study the structural properties of the prepared glass system. Different structural groups such as $[$BO${}_3$$]$, $[$BO${}_4$$]$, $[$MoO${}_4$$]$ and $[$MoO${}_6$$]$ have been detected in the amorphous network. The presence of non-bridging oxygens, bridging oxygens and change of coordination number has been discussed. The optical absorption spectra are recorded in the wavelength range 200-800 nm and optical band gap is calculated which has shown strong dependence on Bi${}_2$O${}_3$/B${}_2$O${}_3$ ratio. The samples have also been tested for their durability by measuring dissolution rate properties using distilled water at 90°C. It has been concluded that increase in the content of Bi${}_2$O${}_3$ in the composition improves durability and $\gamma$ ray shielding properties of the samples.