Magnetic and dielectric properties of Ni0.5Zn0.5Fe2O4/barium titanate (BaTiO3) ceramic composites prepared by an in situ sol–gel method

Ferrimagenitc/ferroelectric Ni0.5Zn0.5Fe2O4 (NZFO)/BaTiO3 (BT) ceramic composites (NBSG) are synthesized via an in situ sol–gel process. The formation of the BaTiO3 layer on the Ni–Zn ferrite particles was performed in two steps, the first formation of sol BaTiO3 precursor layer and then heat treatment at high temperature. The morphology and microstructure of the ceramic composites were studied by the field-emission scanning electron microscope, X-ray diffraction measurements are used to demonstrate the phase change with different molar ratio of NZFO:BT, and their magnetic and dielectric properties of the composites have been investigated by a M–H loop measurement and RF impedance/material analyzer. Results show that the NZFO particles are well surrounded naturally by the perovskite BT layer which could help to avoid the aggregation of NZFO phase, and also in this structure, the interactions between the two constituent phases endow the ceramic composites with both good magnetic and dielectric properties at high frequency.