The Antiferroelectric ↔ Ferroelectric Phase Transition in Lead‐Containing and Lead‐Free Perovskite Ceramics
A comprehensive review on the latest development of the antiferroelectric ↔ ferroelectric phase transition is presented. The abrupt volume expansion and sudden development of polarization at the phase transition has been extensively investigated in PbZrO3‐based
perovskite ceramics. New research developments in these compositions, including the incommensurate domain structure, the auxetic behavior under electric fields in the induced ferroelectric phase, the ferroelastic behavior of the multicell cubic phase, the impact of radial compression, the
unexpected electric field‐induced ferroelectric‐to‐antiferroelectric transition, and the phase transition mechanical toughening effect have been summarized. Due to their significance to lead‐free piezoelectric ceramics, compounds with antiferroelectric phases, including
NaNbO3, AgNbO3, and (Bi1/2Na1/2)TiO3, are also critically reviewed. Focus has been placed
on the (Bi1/2Na1/2)TiO3–BaTiO3 solid solution where the electric field‐induced ferroelectric phase remains
even after the applied field is removed at room temperature. Therefore, the electric field‐induced antiferroelectric‐to‐ferroelectric phase transition is a key to the poling process to develop piezoelectricity in morphotropic phase boundary (MPB) compositions.
The competing phase transition and domain switching processes in 0.93(Bi1/2Na1/2)TiO3–0.07BaTiO3 are directly imaged
with nanometer resolution using the unique in situ transmission electron microscopy (TEM) technique.