Impact of ZnO on the Physical and Optical Properties of PbO-B2O3 Glasses

The structure of the xZnO-30PbO-(70 - x)B2O3 (x = 5-20 mol%) glass system is investigated by analysing the physical parameters like molar volume and density. An increase in density (5.31-5.7 g/cm(3)) and consistent decrease in molar volume (20.95-20.03 cm(3)/mol) of glass samples is observed with the rise in ZnO content. The X-ray diffraction pattern confirms the amorphous nature of glass samples. The ultraviolet-visible spectroscopy technique is utilized to detect changes in optical parameters, like optical band gap and refractive index. The results depicted a reduction in optical band gap (2.63-2.41 eV) with an increase in ZnO content. Other parameters, such as oxygen packing density, ionic behaviour and average boron-boron separation of prepared glasses, have also shown a variation with a change in ZnO content. Infrared Spectroscopy measurements confirm the change of borate coordination from trigonal BO3 to tetrahedral BO4.