Structural, dielectric, impedance, and modulus spectroscopy of BaSnO3-Modified BiFeO3

A BaSnO3-modified BiFeO3 compound (i.e., Bi0.95Ba0.05Fe0.95Sn0.05O3) was synthesized by a cost-effective mixedoxide reaction method at 850 degrees C. The solubility of 5% BaSnO3 in BiFeO3 (BFO) and the formation of a singlephase compound in the rhombohedral structure was checked by the Rietveld refinement method using the Xray diffraction data. The analysis of Fourier transform infrared (FTIR) spectra reconfirmed the formation of the compound. The temperature-dependent dielectric spectrum for the sample exhibits a broad anomaly at 190 degrees C, which seems to be the superposition of three Gaussian peaks corresponding to the Maxwell-Wagner effect, as well as the oxygen-vacancy-induced Fe2+/Fe3+ and Sn2+/Sn4+ redox mechanism. A sharp peak at 350 degrees C corresponds to the magnetic reordering around the Neel temperature. Complex impedance spectroscopy along with modulus analysis confirmed the deviation from Debye-type behavior. The Cole-Cole model was used to resolve the components contributing to the loss tangent. Different models of electrical conduction were used to explain the conduction mechanism in the material. The existence of ferroelectricity in the sample was confirmed from the study of the room-temperature P-E loop. The addition of 5% BaSnO3 to BFO resulted in a 10-fold increase in the dielectric constant and the polarization accompanied by reduced tangent loss, making it attractive for device applications.