Correlation of magnetic and dielectric relaxation to perovskite/spinel structural phase transition in Bi0.9La0.1FeO3–Fe3O4 bi-phase composites

Nanocomposites are widely investigated nowadays due to their vast applications in multifunctional devices. La-doped Bi0.9FeO3 is considered as potential candidate to be utilized in multiferroic applications. However, limitations of this composition include weak magnetic and magnetoelectric response. To overcome weak magnetic response of this material, a series of nanocomposite samples is presented here by combining it with optimized Fe3O4 contents. X-ray diffraction patterns confirm the cubic structure of Fe3O4 belonging to space group Fd 3‾ m and the rhombohedral-type perovskite crystal structure of Bi0.9La0.1FeO3 having space group R3m. Field emission scanning electron microscopy reveals spherical shapes of nanograins. High dielectric constant with fewer energy losses revealed for pure Bi0.9La0.1FeO3 composition, while saturation magnetization and remanent magnetization were increased with the addition of Fe3O4 phase into Bi0.9La0.1FeO3. Enhanced magnetic properties with moderate dielectric properties of 0.6Bi0.9La0.1FeO3+0.4Fe3O4 make it a prominent and potential candidate to be utilized in memory storage devices.