Preparation and characterization of BaTiO3+MgCuZnFe2O4 nanocomposites

MgCuZn ferrite and BaTiO3 powders with the crystallite sizes 88 nm and 82 nm were prepared using a high energy mechanical milling and sintering method. The prepared powders were characterized using X-ray diffractometer (XRD), Fourier transform infrared spectrometer and scanning electron microscope (SEM). The nanopowders were mixed to obtain the composites with composition xBaTiO3+(1−x)Mg0.48Cu0.12Zn0.4Fe2O4 (where x=0-1) using a mechanical milling. The presence of ferroelectric (BaTiO3) phase and ferrimagnetic (MgCuZn ferrite) phase has been confirmed using XRD and SEM. Ferroelectric hysteresis loops and magnetic hysteresis loops have been recorded at room temperature. In polarization-electric-field curves (P-E), the remanent polarization and coercive fields display little asymmetry. When the amount of ferrite phase is increased, the ferroelectric coercive field also increases. The saturation magnetization decreases with an increase of phase fraction of BaTiO3, because the interaction between magnetic grains is weakened by the existence of nonmagnetic (ferroelectric) phase that is distributed in the magnetic phase. The electrical properties were measured on the composites at 1 MHz. The static magnetoelectric (ME) voltage coefficient (dE/dH)H was measured by change in ME output voltage with respect to dc bias magnetic field at a constant applied magnetic field.