Thermal, structural and electrical properties of alkali-vanado-bismuth-tellurite glasses

The glasses of composition 20TeO2-15Bi2O3-(65-x)V2O5-xLi2O (x=10,15,20 and 25 mol%) have been prepared using the conventional melt quenching technique and their thermal structural and electrical properties were investigated through differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) and Impedance spectroscopy, respectively. The glass transition temperature increases with Li2O content and their values ranging from 250 to 274°C. The difference between the crystallization temperature and the glass transition temperature, ΔT=Tc-Tg, have also been found that increasing with Li2O content. The increasing glass transition temperature and ΔT values are indicated that the increase of the thermal stability and rigidity of the glasses with increasing Li2O. The high temperature electrical conductivity has been analyzed using Mott’s small polaron hopping model and activation energy values were determined.