fig8

Figure 8. Schottky barrier formation at the dielectric-substrate interface enables electric field redistribution and enhanced BDS. (A) Cross-sectional STEM images of BCZT_OD/BCZT//(1P) and BCZT/BCZT_OD//(1P) heterostructures, accompanied by corresponding lattice ball-and-stick models; (B) Energy band diagram of the BCZT/BCZT_OD//(1P) structure under forward bias, depicting the metal-semiconductor-dielectric configuration and the formation of a Schottky barrier at the interface. (C) Schematic illustration of W_rec in different types of P-E loops. High W_rec is achieved by suppressing the negative-side FE contribution, enabling improved ESP. BCZT: Ba_0.7Ca_0.3Zr_0.2Ti_0.8O₃; BCZT_OD: oxygen-deficient BCZT. This figure is quoted with permission from Sun et al.^[88]. BDS: Dielectric breakdown strength; STEM: scanning transmission electron microscopy; ESP: energy storage performance; FE: ferroelectric; BCZT: 0.5Ba(Zr_0.2Ti_0.8)O₃-0.5(Ba_0.7Ca_0.3)TiO₃; NSTO: Nb-doped SrTiO₃.