Synthesis and characterization of CoFe2O4–Ba0.9Sr0.1TiO3 magnetoelectric composites with dielectric and magnetic properties

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2009-11, Vol.97 (3), p.575-580
• Main Authors: Kanamadi, C. M., Kim, J. S., Yang, H. K., Moon, B. K., Choi, B. C., Jeong, J. H.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Coefficients; Condensed Matter Physics; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dielectric properties; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Domain effects, magnetization curves, and hysteresis; Electric potential; Exact sciences and technology; Exchange and superexchange interactions; Ferrite; Machines; Magnetic fields; Magnetic properties; Magnetic properties and materials; Magnetically ordered materials: other intrinsic properties; Magnetization curves, magnetization reversal, hysteresis, barkhausen and related effects; Magnetomechanical and magnetoelectric effects, magnetostriction; Manufacturing; Materials science; Nanotechnology; Optical and Electronic Materials; Permittivity (dielectric function); Physics; Physics and Astronomy; Processes; Saturation (magnetic); Surfaces and Interfaces; Thin Films
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-009-5254-7

Magnetoelectric composites of CoFe 2 O 4 ferrite (CFO) and 10 mole % strontium doped BaTiO 3 (BSTO) were synthesized by the solid state reaction method. The presence of two phases in the composite ( x )CoFe 2 O 4 +(1− x )Ba 0.9 Sr 0.1 TiO 3 ( x =0.15, 0.30 and 0.45) was confirmed by XRD and FESEM. The relative dielectric constant with variation of frequency and temperature was studied. The magnetic hysteresis behavior was studied to find the response of CoFe 2 O 4 ferrite to the applied magnetic field. The saturation magnetization decreases with increase of the phase fraction of BSTO in the composites, because the interaction between magnetic grains is weakened by the existence of nonmagnetic BSTO phase distributed in the magnetic phases. All composites after post calcination in oxygen were electrically and magnetically poled to exhibit a significant magnetoelectric effect. A maximum magnetoelectric voltage coefficient of about 0.826 mV/cm Oe was observed for the x =0.15 composite at room temperature.