fig16

Figure 16. Core-shell grain structures enhance dielectric and ESP in lead-free RFE ceramics. (A-C) Core-shell microstructure and properties of BNT-KTaO₃-0.02wt% Li₂CO₃ ceramics: (A) grain morphology and schematic illustration, (B) high-angle annular dark-field (HAADF) image with corresponding EDS elemental mapping, and (C) P-E loops alongside ESP. This figure is quoted with permission from Xue et al.^[139]; (D-F) Ultrahigh ESP in KNN-based RFE ceramics with core-shell grains: (D) grain morphology, (E) EDS mapping, and (F) P-E loops of 0.85KNN-0.15Sr_0.7Nd_0.2ZrO₃-0.03Ag(Nb_0.45Ta_0.55)O₃ ceramics. This figure is quoted with permission from Chai et al.^[141]. ESP: Energy storage performance; RFE: relaxor ferroelectric; BDS: dielectric breakdown strength; BNT: (Bi_0.5Na_0.5)TiO₃; KNN: (K_0.5Na_0.5)NbO₃.