MDSC, electrical conductivity and optical absorption studies of 40B_2O_3-20CdO-(40-x)Bi_2O_3-xLi_2O glasses

摘要

Quaternary glasses with composition 40B_2O_3-20CdO-(40-x)Bi_2O_3-xLi_2O where 0 <= x <= 40 were prepared by melt quench technique. The density of the glass samples which is evaluated by Archimedes method showed that the density increases with Bi_2O_3 content. The modulated differential scanning calorimetry (MDSC) studies have been done on these samples to evaluate various thermo dynamical parameters. The value of glass transition temperature (T_g) decreases with the Li_2O content. The dc electrical conductivity studies revealed that the conductivity in these glass samples increases with Li_2O content, where as the activation energy decreases. Theoretical optical basicity values decreases with Li_2O content The optical absorption studies revealed that the cutoff wavelength increases while optical band gap energy (E_(opt)) and Urbach energy (ΔE) decreases with increase of Li_2O content. The E_(opt) values of these glasses are found to be in the range 2.848-3.258 eV where as the values of ΔE lies in the range 0.21—0.33 eV.