Synthesis and Characterization of CoFe2 O 4/BaTiO3 Multiferroic Composites

Three composite modes of CoFe2 O (4)/BaTiO3 (CFO/BTO) were created with appropriate stoichiometric proportion. They are nitrate solution of CFO mixed with BTO (SCB), self-propagating precursor of CFO mixed with BTO (PCB), and the made-up CFO mixed with BTO (MCB) separately. The microstructural, ferroelectric, and ferromagnetic properties of SCB, PCB, and MCB bulk composites were investigated. SCB, PCB, and MCB bulk composites with a molar ratio of 2:8 were calcined at 1020, 1120, and 1160 C-ay, respectively. And X-ray diffraction (XRD) analysis showed that they all correspond to the CFO with cubic spinel structure and the BTO with tetragonal perovskite structure. The formation temperature of BTO with hexagonal structure is related to the distance of inter-diffusion and Co (2+) concentration in the CFO/BTO bulk composite. The wet chemical routing is of benefit to inhibit the agglomeration of the BTO in the CFO/BTO bulk composite. The maximum polarization of 5.24 mu C/cm (2) was received in the MCB bulk composite sintered at 1160 C-ay with a molar ratio of 1:9. The maximum saturation magnetization of 31.609 emu/g and the remnant magnetization of 10.336 emu/g were obtained in the MCB bulk composite sintered at 1160 C-ay with a molar ratio of 4:6. The threshold ferromagnetic phase content of percolation which has an effect on the MCB bulk composite is less than 40 mol %.