Electrical properties of Zr4+-substituted Mg-Zn ferrites

Electrical conductivity and thermoelectric power measurements were carried out on Mg-Zn ferrites with a range of compositions. Temperature variation of dc resistivity exhibited a break at the Curie temperature. Variation of the Seebeck coefficient from room temperature to 700 K revealed n-type conductivity for the entire system. Activation energies from mobility data agreed with those from resistivity data. Fermi energies calculated from thermoelectric power data agreed with activation energies in the Fermi region but part of the energy was associated with the generation of electrons and part with the hopping of electrons between equivalent sites. 14 refs.