Optical and structural properties of yttrium doped zinc lead borate glasses

Abstract

A series of glass samples of the composition 60 % B2O3 - 35 % Pb3O4 – (5-x) % ZnO – x % Y2O3 with x = 0, 0.5, 1, 1.5, 2, 2.5, and 3 was prepared by the melt quenching technique. The amorphous nature of the prepared samples was confirmed by X-ray diffraction technique. The structural changes in the glass network were inspected by the density and molar volume measurements, as well as by the FT-IR analysis. The density of the prepared samples was realized to decrease while the molar volume increased with the more addition of Y2O3. Some theoretical parameters were evaluated for a better understanding of the glass structure such as, glass and oxygen packing densities, average crosslink density, number of bonds per unit volume, bond stretching force and average single bond strength. FT-IR analysis was employed to investigate the existence of different structural borate units and estimating the N4 ratio. The UV–Vis absorbance spectra was measured and employed to estimate the optical band gap energy. The band gap energy was found to firstly decreased with increasing of the Y2O3 content and then revert back to increase in the highest yttrium doped sample. The Urbach energy, refractive index, molar refraction, molar polarizability and optical basicity were also calculated and discussed.