Characterization and transport properties of V 2O 5–Fe 2O 3–TeO 2 glasses

Abstract

IR, DSC, density and molar volume, and dc conductivity of the glasses in V 2O 5–Fe 2O 3–TeO 2 system were reported. The network structure for the glass compositions with 65 and 62.5 mol%, V 2O 5 is built up of VO 5 polyhedra, while the other glass compositions consist of VO 4 polyhedra. Density and glass transition temperature were observed to decrease with an increase in V 2O 5 content. The glasses had conductivities ranging from 3.31 × 10 −3 S m −1 to 2.88 × 10 −2 S m −1 at 400 K for V 2O 5 = 50–65 mol%. The electrical conductivity was confirmed to be due to adiabatic small polaron hopping. The hopping carrier mobility varied from 0.587 × 10 −5 cm 2 V −1 s −1 to 6.904 × 10 −5 cm 2 V −1 s −1 at 400 K. The carrier density was evaluated to be 2.997 × 10 19–7.298 × 10 19 cm −3. The conductivity was primarily determined by hopping carrier mobility.