AC conductivity and dielectric properties of SiO2–Na2O–B2O3–Gd2O3 glasses

Abstract

Abstract The present paper studies the dielectric properties and ac conductivity of sodium borosilicate glasses doped with varying concentrations of Gd2O3, while maintaining the SiO2:Na2O:B2O3 ratios constant for all compositions. The samples were prepared using rapid quenching method. Their dielectric and electrical properties were measured in the frequency range (102–106 Hz) and temperature range (298–523 K). Experimental results showed that all dielectric and electrical properties are dominated by mole% of Gd2O3. The decrease and increase in these properties were found to be due to formation of short range ordered structure and non-bridging oxygen, respectively. Different models were suggested to describe the conduction mechanism of the investigated compositions based on mole% of Gd2O3. Correlated barrier hopping model (CBH) was suggested to describe the conduction mechanism of 0–2.52 mole% Gd2O3 doped – samples. While, overlapping large polaron tunneling (OLPT) model was applied to describe conductivity of 2.83 mole% Gd2O3 doped sample. Interestingly, an inverse – OLPT model was suggested to describe the conduction mechanism of composition doped with 3.13 mole% of Gd2O3.