Structural, dielectric, magnetic and magnetoelectric studies of (1-x) BaFe12O19-x BiFeO3 composites

Abstract

The synthesis of multiferroic (1-x) BaFe12O19-x BiFeO3; (x = 0.05, 0.08, 0.10) composites was carried out with solid state reaction. The XRD data confirmed the formation of the composites with phases of both compounds. The low values of Rietveld refinement parameters along with modified lattice parameters of both hexaferrite and multiferroic phase reconfirmed the amalgamation of phases. FESEM with EDX were utilized for morphological study and elemental compositional analysis in the composites. The dielectric constant and tanδ both parameters showed typical low frequency dispersion. A mild anomaly in dielectric constant and tangent loss is quite noticeable near to magnetic transition temperature (TN) of BiFeO3 suggests the possible occurrence of magnetoelectric effect in prepared composite system. The fitting of AC conductivity data suggested the OLPT (overlapping large polaron tunneling) conduction process in the composite system. The saturation magnetization (Ms) showed a decreasing trend with increment of BiFeO3 content in composites owing to substituted Fe3+ ion in spin-up state. Coercivity (Hc) found in good agreement with magnetocrystalline anisotropy of hexaferrite phase. The improvements in magnetoelectric coupling coefficient of barium hexaferrite were clearly noticeable with the introduction of BiFeO3 phase owing to piezoelectric coefficient and magnetostriction of ferroelectric and ferrite phases respectively.