Electron microscopy study of ferroelectric domains and microstructural defects in Bi- and Zn-modified Pb(Ni1/3Nb2/3)O3-PbZrO3-PbTiO3 piezoelectric ceramics

Ferroelectric domain configurations and microstructural defects in the Bi- and Zn-modified Pb(Ni
_1/3
Nb
_2/3
)O
₃
-PbZrO
₃
-PbTiO
₃
piezoelectric ceramics were investigated by transmission electron microscopy (TEM) and selected area electron diffraction. In the samples with tetragonal symmetry, labyrinthic domain configurations with 90deg a-c domains were observed besides the herringbone-like configuration, parallel band-shaped and/or wedge-shaped domains. Polar nanodomains with local random contrast were observed in the samples with rhombohedral symmetry but close to the paraelectric phase region, and the effects of electron beam irradiation on the local random diffraction contrast were also studied. Microstructural defect such as anti-phase boundaries in this piezoelectric system was also revealed by TEM.