Effect of octahedral tilting on antiferroelectric phase stabilization in (1-x)NaNbO3-xCdTiO3ceramics

Abstract

In the present work, a unique case for the stabilization of the antiferroelectric phase in NaNbO3 has been presented, where the desired results were obtained in spite of it defying the set pattern predicted by researchers to date for achieving similar results. Antiferroelectric phase stabilization of NaNbO3 was achieved with doping of 1% CdTiO3, which is much lower compared to other dopants reported earlier. From the Rietveld refinement of x-ray diffraction (XRD) patterns, structural changes with respect to octahedral tilting were found to be responsible for the increase in energy barrier required for stabilizing antiferroelectric P over ferroelectric Q phase in (1-x)NaNbO3-xCdTiO3 ceramics. Temperature-dependent dielectric properties implied a shift in Curie temperature with an increase in CdTiO3 concentration. P-E hysteresis loop measurement demonstrated a square-shaped ferroelectric loop for NaNbO3 ceramic, while the antiferroelectric double hysteresis loop was observed for composition x = 0.01 and x = 0.02. The results were verified by observing characteristic superlattice peaks in the XRD patterns. © 2020 IOP Publishing Ltd.