Dielectric, ferromagnetic and maganetoelectric properties of BaTiO3–Ni0.7Zn0.3Fe2O4 composite ceramics

Lead-free magnetoelectric composite ceramics (1 − x)BaTiO3–xNi0.7Zn0.3Fe2O4 (x = 0.15, 0.3, 0.45) were successfully prepared by conventional oxide ceramic process. The tetragonal perovskite BaTiO3 and cubic spinel Ni0.7Zn0.3Fe2O4 were confirmed by X-ray diffraction. The dielectric behaviors of all composite samples show a normal response to the increasing measurement frequency and Ni0.7Zn0.3Fe2O4 ferrite content. Well defined ferromagnetic hysteresis loops and obvious magnetoelectric coupling effect are observed in the composite ceramics. The influence of applied dc bias magnetic field and Ni0.7Zn0.3Fe2O4 ferrite content on the magnetoelectric coupling responding voltage is investigated. The strongest peak magnetoelectric coupling voltage coefficient is 124 μV/cm Oe when x = 0.3, which corresponds to the maximum magnetoelectric coupling responding voltage of 200 μV.