Effect of iron on the electrical properties of lead–bismuth glasses

Journal of Materials Science (Impact Factor: 2.37). 11/2009; 44(21):5760-5767. DOI: 10.1007/s10853-009-3807-y


Semiconducting oxide glasses of the system (80−x)Bi2O3–20PbO–xFe2O3, where x=5, 10 and 15mol.%, were prepared and investigated for dielectric properties in the frequency range 120–100KHz and temperature
range 300–550K. 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. The ac conductivity results suggest that the correlated barrier hopping
(CBH) is dominant in ac conductivity.

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