Effect of iron on the electrical properties of lead–bismuth glasses
ABSTRACT 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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ABSTRACT: Glasses of the 0.5Er3+/2.5Yb3+ co-doped (40Bi2O3–20GeO2–(30 − x)PbO–xZnO–10Na2O system where x = 0.0, 5, 10, 15, 20, 25, and 30 mol%) have been characterized by FT-IR spectroscopy measurements to obtain information about the influence of ZnO-substituted PbO on the local structure of the glass matrix. The density and the molar volume have been determined. The influences of the ZnO-substituted PbO on the structure of glasses have been discussed. The dc conductivity measured in the temperature range 475–700 K obeys Arrhenius law. The conductivity decreases while the activation energy for conduction increases with increase ZnO content. The optical transmittance and reflectance spectrum of the glasses have been recorded in the wavelength range 400–1100 nm. The values of the optical band gap E opt for all types of electronic transitions and refractive index have been determined and discussed. The real and imaginary parts ε1 and ε2 of dielectric constant have been determined.Journal of Materials Science - J MATER SCI. 01/2010; 45(7):1837-1845.