Stabilization of the morphotropic phase boundary in (1 − x)Bi0.5Na0.5TiO3–xBaTiO3 ceramics through two alternative synthesis pathways

Abstract

In this work, we report the influence of synthesis conditions on the (1 − x)Na0.5Bi0.5TiO3–xBaTiO3 (BNT–BT) system, obtained by the conventional solid-state reaction method with a mechanochemical activation step through two alternative synthesis routes on piezoelectric properties. Samples were characterized by X-ray diffraction (XRD), Raman microspectroscopy and scanning electron microscopy (SEM). It was confirmed that the stabilization of a morphotropic phase boundary (MPB) meaningfully improved the piezoelectric activity. Here, we report that the stabilization of the morphotropic phase boundary (MPB) region in the BNT–BT ceramic systems depended on the selected synthesis pathway. Indeed, samples prepared by the direct mechanochemical activation of all mixed BNT–BT reactants showed a correlation between dielectric and ferroelectric properties and a clear sequence in the permittivity values.