Structural and electrical properties of four folded layered BaBi₂Sb₂Ti₄O₁₅ compound

Abstract

BaBi₂Sb₂Ti₄O₁₅, a four-fold layered structured ceramic compound is synthesized by the mixed oxide process at sintering temperature 875 °C. The structural and electrical properties of the material measured in a broad temperature (25–500 °C) and frequency (10³–10⁶ Hz) range are presented here. From the preliminary X-ray structural analysis, it is confirmed that this compound has an orthorhombic structure. The temperature and frequency-dependent dielectric constant of the material is observed. Modified Curie Weiss’s law explains the extent of diffusivity observed in a phase transition. The presence of grain and grain boundary effects is confirmed from the Nyquist plots. Non-Debye-like relaxation is noticed from complex impedance and modulus analyses. Reduction in grain resistance is noticed with the enhancement of temperature indicating the existence of negative temperature coefficient of resistance (NTCR) properties in the compound. It is concluded from the above results that this compound may have wide applications in electronics as well as high-temperature devices.

Keywords:

• X-ray diffraction
• dielectric
• impedance spectroscopy
• complex modulus spectroscopy