A Procedure for the Extraction of Intrinsic AC Conductivity and Dielectric Constant of N87 Mn–Zn Ferrite Samples Based on Impedance Measurements and Equivalent Electrical Circuit Modeling

The Dy-Ho doped Mn-Zn Ferrite nanoparticles have been synthesized by solution combustion method using mixture of fuels as glucose and urea. The synthesized samples of structural properties were characterized through XRD (X-ray diffraction) and dielectric properties were studied through impedance analyzer. The XRD patterns of all samples confirms the spinel cubic structure having space group Fd3m. Further all synthesized samples reveal the single-phase formation without any secondary phase. The lattice parameters and hopping lengths were increases with increase of Dy-Ho concentration. SEM micrographs shows the porous nature for all samples. The crystallite size increases with increase of Dy-Ho concentration. The Dielectric properties of all the samples were explained by using Koop’s phenomenological theory. The real part of dielectric constant, imaginary part of dielectric constant and dielectric loss tangent were decreases with increase of frequency. Th AC conductivity increases with increase of frequency. The real part of impedance spectra decreases with increase of frequency for all samples. The Cole-Cole plots shows the one semicircle for all samples. The high ac conductivity and low dielectric loss observed for all samples at high frequency region and this samples are reasonable for power transformer applications at high frequencies.

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Electrical transport properties of V2O5-added Ni–Co–Zn ferrites

Journal of Advanced Dielectrics ◽

10.1142/s2010135x21500259 ◽

2021 ◽

Author(s):

M. Firoz Uddin ◽

M. Samir Ullah ◽

S. Manjura Hoque ◽

F. A. Khan ◽

A. A. Momin ◽

...

Keyword(s):

Dielectric Constant ◽

Electrical Transport ◽

Ac Conductivity ◽

Complex Impedance ◽

Frequency Region ◽

Dielectric Constants ◽

Bulk Property ◽

Electrical Transport Properties ◽

Polarization Model ◽

Zn Ferrite

Frequency-dependent dielectric constant, dielectric loss, AC conductivity values and complex impedance spectra of V2O5-added Ni–Co–Zn ferrites (Ni[Formula: see text]Co[Formula: see text]Zn[Formula: see text]Fe2O4 + [Formula: see text]V2O5, where [Formula: see text] = 0, 0.5, 1 and 1.5 wt.%) have been investigated at room temperature. The dielectric properties of the samples follow the Maxwell–Wagner polarization model. An inverse relationship was found between dielectric constant and AC electrical resistivity for all the samples. The dielectric constants decreased with the addition of V2O5, while the electrical resistivities of V2O5-added Ni–Co–Zn ferrites are found to be larger than that of pure Ni–Co–Zn ferrite. The AC conductivity was reduced with the addition of V2O5 to Ni–Co–Zn ferrite at lower-frequency region. However, AC conductivity shows a sharp increase at higher-frequency region, which could be attributed to the enhancement of electron hopping between the Fe[Formula: see text] and Fe[Formula: see text] ions in the ferrite matrix due to the activity of the grains. The complex impedance spectroscopy results through Cole–Cole/Nyquist plot have demonstrated a single semicircular arc. It indicates that conduction mechanism takes place predominantly through the grain/bulk property, which could be ascribed to the larger grain size of V2O5-added Ni–Co–Zn ferrites.

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