Influence of B2O3 and Li2O on Physical, Thermal and Spectroscopic Properties of Bi2O3-B2O3-CdO-Li2O Glass System

Bismuth borate-based glasses with compositions BiBCL: 40Bi(2)O(3)-(40-X) B2O3-20CdO-XLi2O where x = 5, 10, 15, 20, 25 mol% were prepared by conventional melt quenching technique. X-ray diffraction (XRD), differential thermal analysis (DTA), UV-VIS absorption spectroscopy, Fourier transforminfrared (FTIR), and Raman spectroscopies were used to analyse the synthesized samples. Through XRD and scanning electron microscopic (SEM) studies, the synthesized glasses' amorphous nature was confirmed. To evaluate the physical and structural characteristics of the glasses, calculations were made for the samples densities, molar volumes, oxygen molar volumes, and oxygen packing densities (OPD). The DTA curve was used to determine the glasses thermal properties, including their glass transition temperature (Tg) and thermal stability. With decreasing B2O3 content, the absorption edge of the glasses shifts towards higher wavelengths, showing the hardness of the glasses. Variation of optical band gap (E-opt), Urbach energy (Delta E) and refractive index (n) of glasses were obtained by optical absorption studies. The FTIR and Raman spectra of the glass system revealed the presence of the structural elements BiO3, BiO6, CdO4, BO3 and BO4 in the glass network. The gradual decrease of B(2)O(3)content in the glass matrix causes the transformation of BO4 structural units to BO3.