Broad-high operating temperature range and enhanced energy storage performances in lead-free ferroelectrics
Weichen Zhao, Diming Xu, Da Li, Maxim Avdeev, Hongmei Jing, Mengkang Xu, Yan Guo, Dier Shi, Tao Zhou, Wenfeng Liu, Dong Wang, Di Zhou
Abstract
Abstract The immense potential of lead-free dielectric capacitors in advanced electronic components and cutting-edge pulsed power systems has driven enormous investigations and evolutions heretofore. One of the significant challenges in lead-free dielectric ceramics for energy-storage applications is to optimize their comprehensive characteristics synergistically. Herein, guided by phase-field simulations along with rational composition-structure design, we conceive and fabricate lead-free Bi 0.5 Na 0.5 TiO 3 -Bi 0.5 K 0.5 TiO 3 -Sr(Sc 0.5 Nb 0.5 )O 3 ternary solid-solution ceramics to establish an equitable system considering energy-storage performance, working temperature performance, and structural evolution. A giant W rec of 9.22 J cm −3 and an ultra-high ƞ ~ 96.3% are realized in the BNKT-20SSN ceramic by the adopted repeated rolling processing method. The state-of-the-art temperature ( W rec ≈ 8.46 ± 0.35 J cm −3 , ƞ ≈ 96.4 ± 1.4%, 25–160 °C) and frequency stability performances at 500 kV cm −1 are simultaneously achieved. This work demonstrates remarkable advances in the overall energy storage performance of lead-free bulk ceramics and inspires further attempts to achieve high-temperature energy storage properties.