Preparation and properties of BaTiO3/ CoFe2O4 composite ceramics

In this study, we report a general process to prepare BaTiO₃, CoFe₂O₄ nanoparticles and other oxides nanoparticles with complex compositions. BaTiO₃, CoFe₂O₄ nanoparticles with particle size less than 50nm were fabricated by a surfactant-assisted ball milling process followed a centrifugal separation. Furthermore, ferroelectric/ferrite composites of (1-x) BaTiO₃/xCoFe₂O₄ (x=0.1, 0.2, 0.3, 0.5) ceramics were then synthesized. The dependence of the ferroelectric and magnetic properties on the content of CoFe₂O₄ has been investigated systematically. No interface reaction was observed in the multiferroic ceramics and the samples have been confirmed with excellent ferroelectric and ferromagnetic properties, of which the maximal remnant polarization value of 1.9μC/cm² and saturation magnetization of 35emu/g were measured at 10% and 30% of CoFe₂O₄, respectively. The dielectric properties of the composites have also been measured as the variation of ferroelectric/magnetic fractions.