Study of structural, dielectric and electrical behavior of (1 − x)Ba(Fe0.5Nb0.5)O3-xSrTiO3 ceramics

▶ In this paper we are focused on single-phase BaFe0.5Nb0.5O3 (BFN) and perovskite solid solution ceramics with compositions of 0.85Ba(Fe0.5Nb0.5)O3 + 0.15SrTiO3 (0.85BFN + 0.15ST) and 0.80Ba(Fe0.5Nb0.5)O3 + 0.20SrTiO3 (0.80BFN + 0.20ST) samples. These ceramics were synthesized by the solid-state reaction method. The XRD patterns of the BFN and BFN-ST at room temperature show a monoclinic phase. Detailed studies of dielectric and impedance properties of the materials in a wide range of frequency (100 Hz-5 MHz) and temperatures (30-270 °C) showed that properties are strongly temperature and frequency dependent. Complex Argand plane plot of ɛ″ against ɛ′, usually called Cole-Cole plots is used to check the polydispersive nature of relaxation phenomena in above mentioned compounds. These compounds are very useful for high voltage capacitors and other applications.