Dependence of structure-property relations on substituent distributions inlead zirconate titanate

The dependence of substituent distributions on A and B sites in rhombohedra l lead zirconate titanate (PZT) was investigated in terms of dielectric spe ctroscopy, polarization switching characteristics and transmission electron microscopy techniques. Decreasing the higher-valence A-site substituent ra dii resulted in higher coercive fields, a smaller decrease in transition te mperatures and the disappearance of relaxor characteristics with respect to the largest A-site substituents La3+. These smaller substituents have enha nced the tendency to exchange on to B sites, resulting in an effective lowe r-valence substituent, 'wavy' domain morphology and 'hard' PZT properties.