Effect of Bi₂O₃ on structure and properties of zinc bismuth phosphate glass

Abstract

Various glasses with different compositions (50 - 2x)ZnO-xBi₂O₃-(50 + x)P₂O₅ (x = 0-20 mol%) were prepared. This study examined the effect of the structure and properties in phosphate glass system according to the change in Bi₂O₃ content in ZnO-Bi₂O₃-P₂O₅ glass. The structure of the glasses was analyzed by Fourier transform infrared (FT-IR) analysis. The FTIR spectra were recorded in the spectral range from 400 to 1400 cm^-1. The structural investigations based on these spectra showed the rapid depolymerization of the phosphate chains with increasing Bi₂O₃ content along with the formation of P-O-Bi bonds. The density, glass transition temperature (T_g), molar volume and optical properties of the glasses were determined from the structural changes in the glasses. T_g, density and molar volume increased with increasing in Bi₂O₃ content in the glass. The optical absorption edge (λ_cut-off) and optical band gap (E_g) were determined from the optical transmittance spectra of the polished samples recorded at room temperature, and found to be associated with structural changes occurring in these glasses with increasing Bi₂O₃ content.