Synthesis and characterization of lead-free sodium doped bismuth titanate

Abstract

In this communication, the convenient solid state technique had been adopted for the preparation of sodium doped bismuth titanate (Bi0.5Na0.5TiO3) ceramic sample in a specified temperature. The classified sample has been found to be possessed a rhombohedral structure as obtained from the XRD analysis having a space group of R-3c (#167). Na dopants in the host bismuth titanate (BTO) are about 53.4 nm and 0.503 %, which being confirmed from the crystalline size of the ceramic sample and lattice strain at microscopic level. The transport properties studied through non-destructive impedance spectroscopy analysis thus revealing the non-Debye as well as the prepared sample confirms negative temperature coefficient resistance (NTCR) behaviour. The thermally activated ac conductivity depicts the activation energy which rises from 10.2 meV to 129.1 meV with simultaneous increase of temperature. The oxygen vacancies and defects leads to conduction mechanism in the thermally activated sample which enables the transport behaviour due to immobile charge carriers. The formation of the asymmetric curves while analysing modulus part of the sample confirm non-Debye conductivity behaviour. The formation of semi-circular arcs in Nyquist as well as Cole-Cole plots suggests the semiconducting nature of the synthesized sample. These materials are useful for sensors, actuators and energy storage devices.