Coexistence of the composition and temperature-induced anomalies in enhancing the dielectric and energy storage properties of (Na0.5Bi0.5)TiO3-based piezoceramics

Abstract

In high-performance piezoelectric ferroelectric materials like Pb(Zr,Ti)O3, significant properties are linked to composition-induced ferroelectric phase boundary, commonly referred to as the morphotropic phase boundary (MPB). Our investigation into (Na0.5Bi0.5)TiO3-Ba(Ti0.98Zr0.02)O3 revealed not only a typical MPB anomaly at a critical composition but also an additional temperature-induced dielectric anomaly associated with the ferroelectric–relaxor transition (TF-R, Td), which occurs near room temperature for the same composition. Consequently, the enhanced properties have been attributed to the presence of both anomalies. High-resolution transmission electron microscopy imaging has demonstrated that the coexistence of these two anomalies leads to the miniaturization of nanodomains, resulting in a high density of interfaces or domain walls.