In situ x-ray diffraction study of the antiferroelectric–ferroelectric phase transition in PLSnZT

In situ x-ray diffraction studies were performed on the PLSnZT antiferroelectric–ferroelectric phase switching ceramic and polycrystalline powder. The crystallography of both the antiferroelectic and electric-field-induced ferroelectric phases were determined for the approximate composition of Pb0.98La0.02(Zr0.55Sn0.33Ti0.12)0.995O3. A preferred antiferroelectric domain structure has been identified and possible mechanisms responsible for the domain structure are presented. A single tetragonal phase has been identified for the room temperature zero-field antiferroelectric material with unit cell dimensions a=4.107 Å and c=4.081 Å. An electric field-induced structure developing at the antiferroelectric–ferroelectric switching field has also been observed and determined to be of rhombohedral symmetry with a=4.105 Å and θ=89.85° indicating a volume increase of 0.49% for the tetragonal–rhombohedral transition.