Abstract
Characterization and electrical properties of vanadium–copper–phosphate glasses of compositions
xV
2O
5–(40−
x)CuO–60P
2O
5 have been reported. X-ray diffraction (XRD) confirms the amorphous nature of these glasses. It was observed that, the density (
d) decreases gradually while the molar volume (
V
m) increases with the increase of the vanadium oxide content in such glasses. This may be due to the effect of the polarizing power strength, PPS, which is a measure of ratio of the cation valance to its diameter. The dc conductivity increases while the activation energy decreases with the increase of the V
2O
5 content. The dc conductivity in the present glasses is electronic and depends strongly upon the average distance,
R, between the vanadium ions. Analysis of the electrical properties has been made in the light of small polaron hopping model. The parameters obtained from the fits of the experimental data to this model are reasonable and consistent with glass composition. The conduction is attributed to non-adiabatic hopping of small polaron.