Effect of Ba and Mn doping on microstructure and multiferroic properties of BiFeO₃ ceramics

Ba, Mn single and co-doped BiFeO₃ ceramics were prepared by combination of solid-state reaction and rapid sintering method. Enhanced ferroelectric and ferromagnetic properties were observed in Ba, Mn co-doped ceramics. Large remnant polarization (Pr∼40.87 μC/cm²) for Bi_0.9Ba_0.1FeO₃ and large remanent magnetization (Mr∼0.834 emμ/g) and coercive field (Hc∼938 Oe) for Bi_0.95Ba_0.05Fe_0.9Mn_0.1O₃ were acquired, respectively. The analysis of structure and valence measured by X-ray diffraction (XRD), Raman spectrum and X-ray photoelectron spectroscopy (XPS) show that an appropriate doping ratio of Ba and Mn ions in BiFeO₃ (BFO) plays an important role in facilitating microstructure distortion and transition, which are favorable for enhancing ferroelectric properties of BFO ceramics. Furthermore, the existence of Fe²⁺ and Mn⁴⁺ ions in Ba-Mn co-doped BFO contributes to the ferromagnetic property. These results demonstrate that ions co-doping is an effective way to modulate the room-temperature ferroelectric and ferromagnetic properties for multiferroic applicability of BFO.