STUDY THE THERMAL AND ELECTRICAL PROPERTIES OF SOME MAGNESIUM-BORO-PHOSPHATE GLASSES CONTAINING VANADIUM OXIDE.

Glasses having the molecular composition 20 MgO - 30 B2O3 - (50-x) P2O5 – x V2O5 –- (x = 0, 5, 10, 15 and 20 mol %) have been prepared by the conventional melt quenching method. The thermal and electrical transport properties of the prepared glasses were thoroughly investigated by using differential thermal analysis technique and LCR meter-bridge with four fixed frequencies.
All the obtained thermal parameters are found to depend on the composition and heating rate. Both the activation energy of glass transition and activation energy of crystallization as well as the thermal stability are found to increase with the gradual increase of vanadium oxide content.
It was found that, all samples exhibit semi-conduction properties and the conduction mechanism was found to be the small polaron hoping at relatively low temperatures while at relatively higher temperatures, the correlated barrier hoping model was found to be dominant. Also, as vanadium oxide was gradually increased, the conductivity, dielectric constant and dielectric loss factor exhibit gradual increase.