Charge distribution around Ba–O and Ti–O bonds in BaTi1−xZrxO3 through powder X-ray diffraction

Abstract

Ferroelectric lead-free BaTi1−xZrxO3 ceramic powder samples with various compositions (x = 0, 0.04, 0.06) have been synthesized by conventional high-temperature solid-state reaction method at 1450 °C for 10 h. Influences of Zr doping on the inter-atomic bonding and charge density distributions inside the lattice structure of BaTiO3 were analyzed through powder X-ray diffraction (XRD) and maximum entropy method. Lattice parameter and cell volume values are found to be increasing with the incorporation of Zr content. Calculated average grain sizes are found to be in the range of 23–28 nm. Maximum entropy mapping of electron density analysis reveals the reduction in ionic nature along Ba–O bond and the enhancement of covalent nature along Ti–O bond. Energy band gap values were determined from ultraviolet–visible (UV–Vis) spectra. Surface morphology and microstructures of the samples were analyzed from scanning electron microscopy (SEM) micrographs. Particles with irregular sizes were observed in all the prepared ceramics. Stoichiometry of the samples was further confirmed by energy-dispersive X-ray spectroscopy (EDAX).