Structure, optical and electrical behaviour of x(2Bi2O3.MnO).(10-x)B2O3 glasses

Abstract Heavy metal glass samples of the system x(2Bi2O3.MnO).(10-x)B2O3 with different compositions were prepared via the conventional method. Differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were utilized to study the thermal behaviour and structure of the glasses. Their physical, optical and electrical properties were studied to characterize the materials. The higher strength of the B O bond than the Bi O bond leads to an increase in the thermal stability of the prepared glass. Both the density and molar volume were increased with an increase in the x value, i.e., the Bi2O3 content. Phase separation is the main feature of the glass structure observed using SEM. Some traces from Bi2O3 and/or MnB4O7 were detected in samples B6 (x = 6) and B3 (x = 3) by XRD. The optical band gap (Eopt) lies between 2 and 3 eV; it increases with a decrease in Bi2O3 content. All glasses exhibited good transmission in the infrared (IR) region, reaching ~45% at ~1750 nm. The activation energies of these prepared compositions were estimated, and their conductivities were found to increase with increasing temperature, revealing their semiconducting character.