Origin of Polarization in Bismuth Sodium Titanate-Based Ceramics

• DOI: 10.1021/jacs.3c13927
• Publication Date: 2024-02-14T09:30:28Z
• Authors: Hangfeng Zhang; Marcin Krynski; A. Dominic Fortes; Theo Graves Saunders; Matteo Palma; Yang Hao; Franciszek Krok; Haixue Yan; Isaac Abrahams
• Keywords: Bismuth; Lone pair; Bismuth titanate

The classical view of the structural changes that occur at ferroelectric transition in perovskite-structured systems, such as BaTiO3, is polarization occurs due to off-center displacement B-site cations. Here, we show bismuth sodium titanate (BNT)-based composition 0.2(Ba0.4Sr0.6TiO3)–0.8(Bi0.5Na0.5TiO3), this model does not accurately describe situation. Such BNT-based systems are interest lead-free alternatives currently used materials a variety piezo-/ferroelectric applications. A combination high-resolution powder neutron diffraction, impedance spectroscopy, and ab initio calculations reveals Ti4+ contributes less than third magnitude overall displacements O2– ions A-site cations, particularly Bi3+, very significant. detailed examination system offers insights applicable understanding transitions other perovskites, those containing lone pair elements.