<abstract xmlns="http://www.w3.org/1999/xhtml"> Two samples of manganese ferrite powder were obtained by the calcination method (sample A) and hydrothermal method (sample B). The crystal structure of the samples has been determined using X-ray diffraction analysis (XRD). The results shown that the sample A has three phases (FeMnO3, Mn2O3 and Fe2O3) and the prevailing phase is FeMnO3 with perovskite structure and the sample B has only a single phase (MnFe2O4). The grain morphology was analyzed by scanning electron microscopy (SEM) and the compositional analysis was done by energy dispersive spectroscopy (EDAX). Measurements of the frequency (f) and temperature (T) dependent complex impedance, Z(f, T) = Z’(f, T) - i Z’’(f, T) of the samples over the frequency range 20 Hz - 2 MHz, at various temperature values from 300C to 1100C are presented. From these measurements, we have shown that the temperature dependence of the relaxation time is of Arhenius type, which suggests that the conduction process is thermally activated. The values obtained for the activation energy Ea, are: 16meV (sample A) and 147.65meV (sample B). Applying complex impedance spectroscopy technique, the obtained results shows the shape of a single semicircle at each temperature over the measurement range, meaning that the electrical process obeys to a single relaxation mechanism. The impedance and related parameters of the electrical equivalent circuit depend on the temperature and the microstructure of samples. The resistive and capacitive properties of the investigated samples are dominated with the conduction and relaxation processes associated with the grain boundaries mechanism.. </abstract>

Two samples of manganese ferrite powder were obtained by the calcination method (sample A) and hydrothermal method (sample B). The crystal structure of the samples has been determined using X-ray diffraction analysis (XRD). The results shown that the sample A has three phases (FeMnO3, Mn2O3 and Fe2O3) and the prevailing phase is FeMnO3 with perovskite structure and the sample B has only a single phase (MnFe2O4). The grain morphology was analyzed by scanning electron microscopy (SEM) and the compositional analysis was done by energy dispersive spectroscopy (EDAX). Measurements of the frequency (f) and temperature (T) dependent complex impedance, Z(f, T) = Z’(f, T) - i Z’’(f, T) of the samples over the frequency range 20 Hz - 2 MHz, at various temperature values from 300C to 1100C are presented. From these measurements, we have shown that the temperature dependence of the relaxation time is of Arhenius type, which suggests that the conduction process is thermally activated. The values obtained for the activation energy Ea, are: 16meV (sample A) and 147.65meV (sample B). Applying complex impedance spectroscopy technique, the obtained results shows the shape of a single semicircle at each temperature over the measurement range, meaning that the electrical process obeys to a single relaxation mechanism. The impedance and related parameters of the electrical equivalent circuit depend on the temperature and the microstructure of samples. The resistive and capacitive properties of the investigated samples are dominated with the conduction and relaxation processes associated with the grain boundaries mechanism..

Complex Impedance of Manganese Ferrite Powders Obtained by Two Different Methods

West University of Timisoara, Faculty of Physics, Bd.V. Pârvan, No. 4, 300223 Timisoara, Romania

West University of Timisoara, Faculty of Physics, Bd.V. Parvan, No. 4, 300223 Timisoara, Romania

West University of Timisoara, Faculty of Physics, Bd.V. Parvan, No. 4, 300223 Timisoara, Romania,

National Institutes for Research and Development in Electrochemistry and Condensed Matter, 300569 Timisoara, Romania

Annals of West University of Timisoara - Physics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

{"article-title":"Complex Impedance of Manganese Ferrite Powders Obtained by Two Different Methods"}

Two samples of manganese ferrite powder were obtained by the calcination method (sample A) and hydrothermal method (sample B). The crystal structure of the...

Complex Impedance of Manganese Ferrite Powders Obtained by Two Different Methods

Pubblicato online: 30 dic 2015

Pagine: 14 - 26

Ricevuto: 23 set 2015

Accettato: 26 nov 2015

DOI: https://doi.org/10.1515/awutp-2015-0203

© 2016

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.