Incommensurate modulated structure and energy storage properties of Pb_1−1.5xLa_x(Zr_0.5Sn_0.4Ti_0.1)O₃ antiferroelectric ceramics

The (Pb, La)(Zr, Sn, Ti)O₃ (PLZST) ceramic with unique antiferroelectric (AFE) properties stands as a highly promising material for diverse functional applications, especially in energy storage and conversion. In this study, Pb_1–1.5xLa_x(Zr_0.5Sn_0.4Ti_0.1)O₃ (x = 0, 0.005, 0.01, 0.015, 0.02, and 0.025) AFE ceramics have been prepared by the conventional solid-state reaction method. The phase structure of the ceramic changed from tetragonal phase at x = 0 to pseudo-cubic phase at x = 0.02 with increasing La doping. Notably, the PLZST-2 ceramics exhibited an enhanced energy storage density of 1.63 J/cm³ and an energy storage efficiency of 82.23%, respectively. The transmission electron microscopy (TEM) analyses revealed the presence of an incommensurate modulated structure in the Pb_1–1.5xLa_x(Zr_0.5Sn_0.4Ti_0.1)O₃, and all the reflections can be expressed as H = ha* + kb* + lc* ± 1/8.5(a* + b*), where h, k, and l are integers. Furthermore, aberration-corrected scanning transmission electron microscopy (AC-STEM) was performed to analyze the atomic-scale structure of the PLZST-2 sample. The annular dark field (ADF) STEM results show the antiparallel arrangement of ion displacement on the atomic scale. The findings of this study enhance our comprehension of the exceptional properties from a structural perspective and hold the potential to facilitate the ongoing advancement of high-performance materials.