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A series of polycrystalline samples of Co1-xZnxFe2O4 where (x = 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) were prepared by the usual ceramic technique. X-ray diffraction patterns confirmed the spinel cubic structure. The diffusion coefficients of oxygen vacancies were estimated from dc conductivity measurements. It was noticed that the diffusion coefficient decreases with increasing Zn2+ concentrations. An increase of temperature increases the diffusion of lattice vacancies. The Curie temperature, lattice parameter and jump length of electrons were studied as a function of Zn2+ concentration. From the correlation between the ionic radius and the radii of octahedral and tetrahedral sites, the theoretical lattice parameters were calculated and suggested cation distribution for the given ferrites was determined.


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Diffusion coefficient of vacancies and jump length of electrons in Co1-xZnxFe2O4 ferrites

Show Author's information M. EL-SAADAWY*( )
Physics Department, Faculty of Science, Kafrelsheikh University, Kafrelsheikh City, Egypt

Abstract

A series of polycrystalline samples of Co1-xZnxFe2O4 where (x = 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) were prepared by the usual ceramic technique. X-ray diffraction patterns confirmed the spinel cubic structure. The diffusion coefficients of oxygen vacancies were estimated from dc conductivity measurements. It was noticed that the diffusion coefficient decreases with increasing Zn2+ concentrations. An increase of temperature increases the diffusion of lattice vacancies. The Curie temperature, lattice parameter and jump length of electrons were studied as a function of Zn2+ concentration. From the correlation between the ionic radius and the radii of octahedral and tetrahedral sites, the theoretical lattice parameters were calculated and suggested cation distribution for the given ferrites was determined.

Keywords:

diffusion coefficient, lattice parameter, jump length and jump rate of vacancies, Curie temperature, cation distribution
Received: 31 May 2011 Accepted: 22 April 2012 Published: 08 September 2012 Issue date: June 2012
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Publication history

Received: 31 May 2011
Accepted: 22 April 2012
Published: 08 September 2012
Issue date: June 2012

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© The author(s) 2012

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