Structural, Electrical and Dielectrical Property Investigations of Fe-Doped BaZrO3 Nanoceramics (original) (raw)
2016, Journal of Electronic Materials
Nanocrystalline samples of BaZr 1Àx Fe x O 3 (x = 0.0, 0.05, 0.10, 0.20, 0.30, 0.40 and 0.50) ceramics were synthesized by the wet chemical sol-gel auto combustion method. The perovskite structured cubic phase formation of BaZr 1Àx Fe x O 3 samples was confirmed by x-ray diffraction (XRD) data analysis. Various structural parameters such as lattice constant (a), unit cell volume (V), x-ray density (q x), and porosity (P) were determined using XRD data. The lattice constant (a), x-ray density (q x) and porosity (P) decrease with an increase in Fe content x. The average particle size was calculated by using the Debye-Scherer's formula using XRD data and was 9-18 nm. The microstructural studies were investigated through scanning electron microscopy technique. Compositional stoichiometry was confirmed by energy dispersive spectrum analysis. The direct current electrical resistivity studies of the prepared samples were carried out in the temperature range of 343-1133 K using a standard two-probe method. The electrical conductivity (r) increases with temperature and Fe concentration. The dielectric parameters such as dielectric constant (e¢) and loss tangent (tan d) were measured with frequency at room temperature in the frequency range 50 Hz to 5 MHz. The dielectric parameters show strong compositional as well as frequency dependences. The dielectric parameters were found to be higher at lower frequency.
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Correlation Between Microstructure and Impedance Properties.docx
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