Heterogeneous antiferroelectric ordering in NaNbO3-SrSnO3 ceramics revealed by direct superstructure imaging

TL;DR

This study uses Dark-Field X-ray Microscopy to visualize antiferroelectric phase heterogeneity in NaNbO3 ceramics, revealing how SrSnO3 stabilizes the phase and enhances structural order, which could improve energy storage materials.

Contribution

It introduces a novel application of Dark-Field X-ray Microscopy for directly imaging superstructure and strain heterogeneity in antiferroelectric ceramics.

Findings

SrSnO3 stabilizes the antiferroelectric phase

Enhanced mesostructural order observed with SrSnO3

Method enables exploration of disorder effects in modulated structures

Abstract

NaNbO3-based antiferroelectric materials offer a promising pathway towards greener and more cost-effective energy storage devices. However, their intrinsic structural instabilities often lead to reduced energy density that compromises their performance and longevity. In this brief communication, we demonstrate how Dark-Field X-ray Microscopy, when carried out on the characteristically weak 1/4{843}pc superstructure reflection, can map the antiferroelectric phase and its strain heterogeneity in typically small, deeply-embedded grains of a NaNbO3 and 0.95NaNbO3-0.05SrSnO3 ceramics, representative of different phase transition behavior. Our results clearly evidences the stabilizing effect of SrSnO3 on the antiferroelectric phase by enhancing the degree of mesostructural order. In doing so, our method establishes a new platform for exploring the impact of disorder on the long-range strain heterogeneity within antiferroelectrics and other materials with modulated crystal structures.