Structural and electrical properties of MoO₃-TeO₂glasses

Abstract

The dc conductivity of MoO3-TeO2 glasses prepared by melt quenching has been investigated in the temperature range 323-473 K. Seebeck coefficient measurements indicate the glasses to be n-type. The conductivity increases with increase of MoO3 content and at 418 K varies from about 6×10-6 to 1×10-8 S cm-1. The conduction is attributed to non-adiabatic hopping of small polarons due to the different valence states, Mo5+ and Mo6+, the existence of which was confirmed from x-ray photoelectron spectroscopy analysis of the glasses. Fourier transform infrared spectroscopic studies show the presence of MoO6, MoO4, TeO3 and TeO4 structural units in the glasses.