Enhanced magnetoelectric response in bismuth-deficient BiFeO3-BaTiO3 ceramics

Abstract

The magnetoelectric response of the bismuth-deficient BiFeO3-BaTiO3 ceramics fabricated using a conventional solid-state reaction method was investigated. We found that a ferromagnetic BaFe12O19 phase is produced as a consequence of bismuth-deficiency (Bi-deficiency) and that the ceramics are 0–3 composites of BaFe12O19 and BiFeO3-based perovskite. An enhanced magnetoelectric response can be achieved in Bi-deficient composites as a consequence of the coupling between magnetostriction in the BaFe12O19 phase and the piezoelectric effect in the BiFeO3-based perovskite phase. In comparison with the composite ceramics prepared using a direct mixing method for the two components, Bi-deficient ceramics have a more uniform distribution of the BaFe12O19 phase in the perovskite matrix and a reduction in dielectric loss and conduction. Thus, the magnetoelectric response of Bi-deficient ceramics is greater than that of ceramics fabricated using a direct mixing method. Our work presents a simple approach for the fabrication of BiFeO3-based composite ceramics with uniformly distributed ferromagnetic particles and enhanced ferromagnetic and magnetoelectric responses.