Phase transition and dielectric properties of (Pb,La)(Zr,Sn,Ti)O3 ceramics at morphotropic phase boundary

Abstract

(Pb0.97La0.02)(Zr75Sn0.25-x Tix)O3 (0.08 ≤ x ≤ 0.11) ceramics at morphotropic phase boundary (MPB) were fabricated by the conventional solid–state reactions, and the major phase was changed from tetragonal antiferroelectric phase to rhombohedral ferroelectric phase (AFET-FER) as the increase of Ti/Sn. The dielectric properties in original states and the poled states were systematically studied. Dielectric constant of the electric-induced AFET poled states was greater than the virgin state, then approached and become less as the compositions moved to FER phase. Moreover, there was a dielectric anomaly for FER poled sample on heating, but not observed in cooling cycle and AFET sample, which was a FE-AFE phase transition confirmed by dielectric constant as functions of temperature and electric field, and the abnormal dielectric behavior become more obviously with electric field increasing. This results are useful to understand the dielectric properties and phase transition in AFE and FE materials.