Introducing Nickel Ions into a Bismuth Boro Tellurite Glass System and Its Effect on Physical and Material Properties

Five bismuth boro tellurite glass samples doped with NiO are synthesized using melt quenching and then their material properties are determined. Structural units are BO 3 , BO 4 , TeO 4 and BiO 6 and Ni-O-Ni linkages, with Ni acting as a network modifier, as shown by Raman spectra. Non-crystalline internal structure of the samples is shown by XRD. Higher NiO concentrations decrease optical band gap energy, as revealed by optical absorption measurements (UV–vis), causing increases in the refractive index, polarizability and optical basicity of the glass system. Positive metallization criterion shows that the glass network structure is that of a non-metal. Internal glass structure showed reduced disorder with doping as evidenced by the lowered Urbach energy. The density, oxygen molar volume and oxygen packing density of the glass samples increased with doping whilst molar volume and cross-link density decreased. Glass-forming ability of the samples increased with doping, as evidenced by the increase in the Hruby’s parameter. A decrease in the temperature range from crystallization temperature to glass transition temperature indicates a reduction in the thermal stability of the doped bismuth boro tellurite system, however the difference remained large (≈100 °C) indicating that the glass samples maintained good thermal stability. Elastic properties increased with the introduction of Ni, increasing the rigidity and strength of the bismuth boro tellurite glass system. Introducing Ni slightly increases radiation shielding ability; shielding surpasses concrete.