Optical Properties of Bismuth Borate Glasses Doped with Zinc and Calcium Oxides

Abstract

Some bismuth-borate oxide glass' samples were prepared by the fast quenching method, where B₂O₃ was replaced with equal concentrations of ZnO and CaO. X-ray diffraction (XRD) was used to examine the internal structure and Fourier transform infrared (FTIR) to identify building units and bonds throughout the studied structural matrices. XRD showed that all samples have short range order structural nature, while FTIR demonstrated some of Zn²⁺ acted as glass network formers and all Bi³⁺ acted as glass. UV-visible measurements and calculations showed a decreasing in the energy band gap from 3.83 eV to 1.73 eV with decreasing B₂O₃ content. Also with decreasing B₂O₃ content, both real refractive index and metallization factor decreased from 3.1 to 1.9 and from 0.56 to 0.71, respectively. For the studied glass' samples, density and molar volume showed inverted behaviors, where the density decreased while the molar volume increases with decreasing B₂O₃.