Effect of ZnSnO3 on dielectric and ferroelectric properties of Sr2Bi4Ti5O18 ceramics

Abstract

AbstractSr2Bi4Ti5O18 is one of the promising candidates for ferroelectric nonvolatile random access memory device applications. Albeit, this ceramic material is not suitable for certain ferroelectric device applications because of the merits and demerits associated with this material. Solid‐solution or composite ceramics in bulk configuration is the better choice to overcome the drawbacks associated with the individual compounds. Concurrently, solid‐solution of functional electro‐ceramics comprising Aurivillius family‐based lead‐free bismuth‐layered structured ceramics (1 − x) Sr2Bi4Ti5O18 (SBT) and x mol% of ilmenite structured ZnSnO3 (ZS) (where x = 0, 5, 10, and 20 mol%) were synthesized via conventional solid‐state reaction route to investigate the effect of ZS on the physical properties of SBT. X‐ray diffraction diffractograms revealed that a single phase was formed maximum up to 5 mol% of ZS in SBT and scanning electron microscopy studies suggested platelike microstructure of the samples. Intriguingly, positive‐up and negative‐down results indicated that the true switchable polarization for the 10 mol% ZS in SBT (10.87 μC/cm2), 33% higher than that of pure SBT ceramics in addition to the lower leakage current density and enhanced dielectric response in the SBT–ZS samples. The observed enhancement in electrical characteristics of SBT–ZS composite ceramics compared to pure SBT highlights the decisive role played by the ZS in lowering the thermodynamic barrier resulting in ease of polarization switching and mitigating the leakage current of SBT ceramics.