ELECTRONIC CONDUCTIVITY IN GLASSES OF THE TEO2-V2O5-MOO3 SYSTEM

Conductivity and redox potential on glasses of the TeO2-V2O5-MoO3 system have been measured. For temperatures between 20 to 200°C, the electronic conductivity proceed by an activated mechanism. Variations of the pre-exponential factor interpreted by the small polaron theory indicate that only the vanadium ions are involved in the conduction mechanism. Cyclic voltamperometry measurements performed on TeO2-V2O5-MoO3 glasses as working electrode show that a 1 V difference between the V+V V+IV and Mo+VI Mo+V redox potentials exists in the glassy material. This correspond to an energy gap which may be to large to allow the electron transition from vanadium to molybdenum ions. © 1990.