The increasing interest in the research on materials with magneto-electric properties has been one of the most challenging tasks for the scientific community in the last years. Specially, the investigation of such materials has been conducted to the development of electronic devices, such as sensors, transducers and memory storage. The magnetoelectric effect presented in certain materials can be explained by taking into account the electrical polarization response due to the application of a magnetic field or magnetization response due to the applied electric field. Multiferroic materials can successfully exhibit these effects, favoring the advent of a class of materials called magnetoelectric multiferroics, which combine ferro/ferri-magnetism and ferroelectricity phenomena. The objective of the present work is to investigatie the structural and dielectric properties of multiferroic ceramic composites based on spinel structure-type NiFe2O4 system. The samples were obtained from the solid-state reaction method, by considering a stoichiometric ratio between the nickel ferrite ferromagnetic and a ferroelectric phase matrix. The obtained results have been discussed considering the influence of the nickel ferrite content on the physical properties of the studied composite.
The authors wish to thank FAPEMIG and CNPq Brazilian agencies and NSF (Grant No. ECCS1002380) for the financial support. R. J. Portugal also thanks the Materials Science Post-Graduation Program (PPGCM), UNESP, Ilha Solteira, Brazil.