Ferroelectric and Magnetic Characterization of Ferroic Pb(Fe0.5Nb0.5)O3 Ceramics

ABSTRACTSingle phase multifunctional materials such as Pb(Fe0.5 Nb0.5)O3 (PFN), where ferroelectric and magnetic order coexist, are very promising and have great interest from the academic and technological points of view. PFN ceramics have been prepared from different kinds of FeNbO4 precursors with either monoclinic or orthorhombic structures. Crystallographic, compositional and surface morphological studies and the temperature-frequency response carried out and reported in previous works are summarized. Ferroelectric hysteretic, magnetic and magnetoelectric behaviors were measured. The remanent polarization (Pr) and coercive field (EC) as functions of temperature and external electric fields (Eext) were determined. Measurements of magnetic susceptibility (χm) exhibited antiferromagnetic order and, above the Núel point near 122 °K, Curie–Weis behavior; whereas a weak ferromagnetic observed from electron paramagnetic resonance (EPR) is discussed. However, magnetoelectric effects were not observed. Ferroelectric and magnetic behaviors, as functions of the kind of precursor used in the preparation, are discussed and correlated with the previous dielectric characterization where microstructural and equivalent circuit models were established using the impedance spectroscopy technique.