Phase formation and magnetic properties of bismuth ferrite-lead titanate multiferroic composites

Abstract

In this study, phase formation and the magnetic properties of bismuth ferrite-lead titanate multiferroic composites were investigated. Multiferroic composites consisting of antiferromagnetic bismuth ferrite (BiFeO3or BF) and ferroelectric lead titanate (PbTiO3or PT) were synthesized by the solid-state sintering method. The presence of pure phase in these composites was confirmed by X-ray diffraction (XRD). The microstructure and magnetic properties were investigated by means of a scanning electron microscope (SEM) and vibrating sample magnetometer (VSM), respectively. Structural transformation from rhombohedral in pure BF to mixed-phase between rhombohedral and tetragonal when added with 50 wt% PT has been revealed from XRD analysis. The magnetic properties are generally seen to reduce with an increase in the content of the PT phase. Interestingly, the M-H hysteresis loop measurements indicated that the composites exhibited superparamagnetic behavior at room temperature for all compositions, a noticeable contradiction to the magnetic behavior earlier reported for the BF-PT solid-solution. © 2012 Springer Science+Business Media, LLC.