Electrical conductivity study of BaSb₄Ti₄O₁₅ compound

Abstract

The lead-free compound of antimony-based new layered structure BaSb₄Ti₄O₁₅ compound is synthesised by high-temperature conventional technique with a calcination temperature of 830 °C. The analysis of X-ray diffraction data shows that the compound had a single-phase orthorhombic crystal system. The scanning electron microscopic analysis of the samples shows a uniform distribution of grains with a smaller number of voids on the surface of the pellet. Generally, different computerized software are used for structural analysis taking powder XRD data. In the process we have attempted to use Jana2006, Qualx, Profex, POWDMULT, FullProf Suit, MAUD and EXPO etc. softwares. It has been found that different softwares give different results. The analysis of structural parameters looks more reliable and consistent with other physical parameters. However, the other possibilities of the structure with large number of experimental data cannot be ruled out. The electrical conductivity of the compound is studied with the help of complex impedance spectroscopy in the frequency range of 1 kHz–10³ kHz and temperature range from 30 °C to 500 °C. The conduction process is a thermally activated phenomenon, which is confirmed by AC conductivity versus absolute temperature graphs. The process of conduction in the studied compound is electronic in lower temperatures and conductivity is due to the hoping of the ions at higher temperatures. The conduction process is due to the hopping and non-Debye type which is confirmed by Jonscher’s universal power law. A study of both AC and DC conductivity study informs the negative temperature coefficient of resistance behaviour. The finding here broadens the family of Sb-modified layered structured material which was a class of ferroelectric with good conductivity values with possible application in the field of optoelectronics as well as in perovskite solar cell.

Keywords:

• Complex impedance spectroscopy
• non-Debye
• NTCR
• activation energy
• AC and DC conductivity

Disclosure statement

No potential conflict of interest was reported by the authors.