Structure, dielectric and relaxor properties of Sr0.7Bi0.2TiO3K0.5Bi0.5TiO3 lead-free ceramics for energy storage applications
Peng Zhao, Bin Tang, Zixuan Fang, Feng Si, Chengtao Yang, Gang Liu, Shuren Zhang
Abstract
Sr0.7Bi0.2TiO3 (SBT) by increasing the proportion and size of polar nano-region. Meanwhile, the BDS remains a high level with x ≤ 0.38 attributed to the addition of KBT with a large band gap. As a result, the 0.62SBT-0.38KBT exhibits a high energy storage density of 2.21 J/cm3 with high η of 91.4% at 220 kV/cm and superior temperature stability (−55 ∼ 150 °C), frequency stability (10 ∼ 500 Hz) and fatigue resistance (105 cycles). Moreover, high pulsed discharge energy density (1.81 J/cm3), high power density (49.5 MW/cm3) and great thermal stability (20 ∼ 160 °C) are achieved in 0.62SBT-0.38KBT. Based on these excellent properties, the 0.62SBT-0.38KBT are suitable for pulsed power systems. This work provides a novel strategy and systematic study for improving energy storage properties of SBT.