Yttrium-doped cobalt nanoferrites prepared by sol-gel combustion method and its characterization.

Ferrites are extremely important magnetic ceramics in the production of electronic components because they reduce the energy losses by the induced currents acting as electrical insulators. Similarly, the spinel-structured cobalt-based ferrites are promising materials for stress, torsion sensors and energy storage applications (anode materials in lithium batteries, fuel cells and solar cells). Therefore, many studies have focused on cobalt ferrites obtained using conventional techniques. Different sintering conditions, types and levels of substitution result in different microstructures and magnetostriction coefficients under a wide range of preparation conditions. Despite many attempts, there are no specific reports on the trivalent substitution of yttrium in cobalt ferrite to the best of our knowledge. In the present study, yttrium-doped cobalt ferrite was prepared with different concentrations to identify the crystallite size with respect to the yttrium concentration, temperature and changes in the structural and electrical properties. In addition, the resistance of the nanostructured yttrium-doped cobalt ferrites nanopowders was analyzed. The resistance was increased by the addition of yttrium to cobalt ferrites.