Effect of SiO2 and Al2O3 on the Spectroscopic and Thermal Properties of Bismuth Borate Glasses

Glass samples from three x Bi2O3- y SiO2 - (100-x-y) B2O3, (Where x = 50 and y = 5, 10, 20) and xBi2O3-ySiO2-zAl2O3- (100-x-y-z) B2O3 (Where x=50, y= 0,5 and 30, z=2,4,6,8) were prepared by melt quenching technique. SiO2, Al2O3 substituted bismuth borate (Bi2O3-SiO2-B2O3, Bi2O3-Al2O3-B2O3, Bi2O3-SiO2-Al2O3-B2O3) glasses were prepared with varying concentrations of SiO2 and Al2O3.the characterization of these glasses was carried out using density measurements. The absorption edge, Urbach energy and transition temperature has been calculated from the optical and thermal analysis respectively. The structural analysis reveals that the glass has BO4, BO3 units as the local structure. The molar volume of glasses has also been calculated from density measurements following Archimedes method, which clearly shows decrease in molar volume of bismuthborosilicate and increase in boroaluminosilicate glasses. DSC and density measurements supports the conclusions drawn from these studies.