High-Temperature Thermoelectric Power Studies of Ni-Mg Ferrites

Abdul Gaffoor, Dachepalli Ravinder

Department of Physics, Osmania University, Hyderabad, India.

DOI: 10.4236/wjcmp.2012.24040                

Abstract

Thermoelectric Power studies of Ni-Mg ferrites having chemical formula Ni_1–xMg_xFeO₄ (x = 0.2, 0.4, 0.6 and 0.8) were investigated from room temperature to well beyond Curie temperature by the differential method. The Seebeck coefficient is negative for all the composition. It clearly speaks that all the considered ferrite compositions behave as n-type semiconductors. Plots of Seebeck coefficient (S) versus temperature shows maximum at Curie temperature. The values of the charge carrier concentration have been computed from the observed values of Seebeck coefficient. The electrical properties of the Ni-Mg mixed ferrites have been measured at room temperature by two-probe method. On the basis of these results an explanation for the conduction mechanism in Ni-Mg mixed ferrites is suggested.

Keywords

Electrical Properties; Sintering; Thermoelectric Power; Ni-Mg Ferrites

Conflicts of Interest

The authors declare no conflicts of interest.

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