European Journal of Applied Engineering and Scientific Research
Abstract
Author(s): S. A. Mastia, A. K. Sharmab, P. N. Vasambekarc
The structural and thermo-electrical properties of Cd2+ and Cr3+ substituted are studied by synthesizing the spinel
solid solutions series CdxMg1-xFe2-yCryO4. Spinel samples of this series with x = 0, 0.2, 0.4, 0.6, 0,8 and 1.0; y = 0,
0.05 and 0.1 were prepared by double sintering ceramic method. X-ray diffraction (XRD) and FTIR absorption
methods are used to obtain the structural characterization. The structural details like: lattice constant, A-O, B-O, rA
and rB have been deduced through XRD data analysis. Lattice constant increases with Cd2+ concentration and
decreases with Cr3+ concentration. These changes in lattice constant are attributed to the difference in ionic radii of
Cd2+, Cr3+ and Fe3+ions. Seebeck Coefficient of each composition was measured in the temperature range 300 K to
750 K. The Seebeck coefficient is negative for all the compositions showing that these ferrites behave as n-type
semiconductors. On the basis of these results, an explanation for the conduction mechanism in Cd2+ and Cr3+
substituted Magnesium ferrites are suggested.
