Fabrication, structure and properties of BaTiO3–BaFe12O19 composites with core–shell heterostructure

(1 − x)BaTiO3–xBaFe12O19 (x = 0.02, 0.04, 0.06, 0.08, 0.10 and 0.12) composites with core–shell heterostructure could be facilely synthesized via combined microwave hydrothermal and sonochemical method in an optimized condition. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that the core–shell heterostructure with a BaTiO3 core and BaFe12O19 shell were successfully prepared. The saturation magnetization of samples increased from 0.51 to 28.61 emμ/g during BaFe12O19 content increases from 0.02 to 0.12, which is higher than the calculated expected values for all samples. A broad dielectric peak appeared in the range of 200 ∼ 300 °C, which shifted toward high temperatures with increasing frequency.