Effect of Dy2O3 on Physical, Properties of B2O3–TeO2–ZnO–Li2O–WO3 Glasses

Effect of Dy2O3 on the properties of borotellurite glasses, (B2O3)0.2–(TeO2)0.22 – x–(ZnO)0.28–(Li2O)0.20–(WO3)0.10–(Dy2O3)x; x = 0.01 to 0.06 has been investigated. Density increased and molar volume decreased with increase of Dy2O3 and they were explained in terms of composition. Glass transition temperature increased and thermal stability decreased with increase of Dy2O3 content. Conductivity increased and its activation energy decreased up to 0.04 mole fraction of Dy2O3 and behaved in opposite way for higher amounts of Dy2O3. These results are ascribed to network changes occurring around 0.04 mole fractions of Dy2O3. For the first time the effect of Dy2O3 on conductivity has been reflected in this fashion. Polaron hopping distance, polaron radius and Debye’s temperature were determined and discussed appropriately.