Investigation of electric field-induced antiferroelectric to ferroelectric phase transition and phase stability of PLZST ceramics

We have prepared antiferroelectric ceramics with compositions of (Pb_0.97 La_0.02) (Zr_1-x-y Sn_yTi_x)O₃(x=0.09 or 0.1; 0.16≤y≤0.38) near antiferroelectric (AFE)tetragonal-ferroelectric (FE)rhombohedral morphotropic phase boundary. The effects of Sn content on electric field-induced AFE→FE switching field E_c, double-hysteresis-loop width ΔE, and temperature-induced FE→AFE phase transition temperature T_FE, AFE→paraelectric (PE) transition temperature T_c are investigated. At constant Ti content x, both T_EF and T_c decrease with increase of Sn content y. Electric hysteresis loop measurement demonstrates an increase of E_c and decrease of ΔE when Sn content y increases. Furthermore, we also find that E_c and ΔE are related with T_FE and T_c. In situ X-ray diffraction under dc bias field shows that symmetry changes from tetragonal phase to rhombohedral phase with an increase of c axis, and an increase of lattice volume.