Structural and DC conductivity studies of borotellurite glasses doped with ZnO, Li2O and Dy2O3

Abstract

Borotellurite glasses mixed with oxides such as ZnO, Li2O and Dy2O3 in definite compositions were synthesized by standard melt quench method. Powder XRD studies confirmed non-crystallinity (glassy) of the prepared samples. FTIR studies have been made to explore the presence of functional groups and various structural units. The formations of BO4, TeO4, BO3, TeO3 etc. units and bending vibrations have been investigated. DC conductivity measurements were done over a wide range of temperature by two probe method. The observed variation with temperature ascribed to semiconducting nature of glasses. High temperature conductivity data has been analyzed in the light of Mott’s (SPH) model and corresponding activation energy of individual glasses has been determined. Conductivity and activation energy, changes positively with Li2O content. Density of states obtained from Mott’s VRH model at lower temperature are in agreement with literature quoted values for similar glasses.