BNT-ST基陶瓷由于其优异的储能性能，如较大的自发极化，高能量效率，良好的弛豫性能等，成为储能陶瓷领域的热门材料而被广泛研究。然而BNT-ST基陶瓷的击穿场强较低，这严重制约了其能量密度的提升。为了提高BNT-ST基陶瓷的击穿场强，引入二段式烧结结合化学包覆SiO₂逐级优化策略。二段式烧结可以有效抑制晶界迁移，并为晶界扩散提供足够的能量，在实现陶瓷致密化的同时，抑制了晶粒长大。二段式烧结结合化学包覆SiO₂不仅能够有效抑制晶粒长大，还能在陶瓷晶界处形成一层具有高击穿势垒的SiO₂，大幅提高了BNT-ST基陶瓷的击穿场强和能量密度。相关研究成果以题为“Enhancing energy storage density of BNT-ST-based ceramics by a stepwise optimization strategy on the breakdown strength”发表在“Journal of the European Ceramic Society”（JCR Q1）上。

Fig. 1. Strategy diagram for achieving excellent energy storage properties via a stepwise optimization strategy combining two-step sintering and chemical coating

Fig. 2. (a) and (b) HR-TEM images of BNT-ST @ Si-TSS powder; (c) TEM images of BNT-ST @ Si-TSS ceramic; (d) EDS line profiles of Si, Bi, Sr and Ti along line AB in (c).

Fig. 3. (a) Unipolar P-E loops of all ceramic samples at room temperature and 10 Hz under 100 kV/cm; (b) unipolar P-E loops of all ceramic samples at different electric fields with room temperature and 10 Hz; (c) maximum W_dis and E_b of all ceramic samples at different electric fields with room temperature and 10 Hz measured up to E_b; (d) W_dis and E_b values relative to different samples.

Fig. 4. (a) Unipolar P-E loops of BNT-ST @ Si-TSS ceramic measured at 120 kV/cm after various cycles. (b) W_dis and η values versus cycles. (c) Unipolar P-E loops of BNT-ST @ Si -TSS ceramic measured at 120 kV/cm over the temperature range from 30 to 140 ℃. (d) W_dis and η values versus temperature.

作者：李欣恒¹，朱超琼^1,*，李世恒，李澳宇，梁岚青，蔡子明^*，冯培忠

链接：https://www.sciencedirect.com/science/article/pii/S0955221924003297

DOI：10.1016/j.jeurceramsoc.2024.04.023