Synthesis and characterization of Cr doped CoFe{sub 2}O{sub 4}

Journal Article · Fri May 06 00:00:00 EDT 2016 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4946148· OSTI ID:22591276

Verma, Kavita ^[1]; Patel, K. R.; Ram, Sahi

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1. Material Science Laboratory, School of Physics, Vigyan Bhawan, Devi Ahilya University, Indore 452001 (India)

Polycrystalline samples of pure and Cr-doped cobalt ferrite (CoFe{sub 2}O{sub 4} and CoCrFeO{sub 4}) were prepared by solid state reaction route method. X-ray diffraction pattern infers that both the samples are in single phase with Fd3m space group. Slight reduction in the lattice parameter of CoCrFeO{sub 4} has been observed as compared to CoFe{sub 2}O{sub 4}. The dielectric dispersion has been explained on the basis of Fe{sup 2+} ↔ Fe{sup 3+} hopping mechanism. The polarizations at lower frequencies are mainly attributed to electronic exchange between Fe{sup 2+} ↔ Fe{sup 3+} ions on the octahedral site in the ferrite lattice. In the present system a part from n-type charge carrier (Fe{sup 3+}/Fe{sup 2+}), the presence of (Co{sup 3+}/Co{sup 2+}) ions give rise to p-type charge carrier. Therefore in addition to n-type charge carrier, the local displacement of p-type charge carrier in direction of external electric field also contributes to net polarization. However, the dielectric constant and loss tangent of CoCrFeO{sub 4} are found to be lower than CoFe{sub 2}O{sub 4} and is attributed to the availability of ferrous ion. CoCrFeO{sub 4} have less amount of ferrous ion available for polarization as compared to that of CoFe{sub 2}O{sub 4}. The impedance spectra reveal a grain interior contribution to the conduction process.

• OSTI ID: 22591276
• Journal Information: AIP Conference Proceedings, Vol. 1728, Issue 1; Conference: ICC 2015: International conference on condensed matter and applied physics, Bikaner (India), 30-31 Oct 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHARGE CARRIERS
CHROMIUM COMPOUNDS
COBALT IONS
COBALT OXIDES
COMPARATIVE EVALUATIONS
CUBIC LATTICES
DIELECTRIC MATERIALS
DOPED MATERIALS
FERRATES
IMPEDANCE
IRON IONS
LATTICE PARAMETERS
PERMITTIVITY
POLARIZATION
POLYCRYSTALS
P-TYPE CONDUCTORS
RELAXATION LOSSES
SYNTHESIS
X-RAY DIFFRACTION