Dielectric, energy storage, and charge-discharge properties of Yb-modified Sr_0.7Bi_0.2TiO₃ relaxor ferroelectric ceramic

Dielectric capacitors have been widely studied in advanced electronics systems due to their rapid discharge rate and high-power density. Among them, relaxor ferroelectrics characterized by nanodomains possess broad application prospects as dielectric materials with high energy density and high efficiency. In this paper, the dielectric characteristics, energy storage performance, and charge-discharge behavior of rare-earth Yb-doped Sr0.7Bi0.2TiO3 ceramics are systematically investigated. The Yb-doped SBT ceramics reduced the grain size, improved the insulation and thermal conductivity, and significantly improved the dielectric breakdown strength. Finally, a high recoverable energy density of 2.32 J/cm(3) and an excellent energy storage efficiency of 92.2% were obtained at 300 kV/cm. In addition, pulsed charge-discharge tests show that Sr0.7Bi0.15Yb0.05TiO3 possesses a rapid discharge rate and high-power density with superior thermal stability. Based on these outstanding characteristics, Sr0.7Bi0.15Yb0.05TiO3 exhibits promising applications in pulsed power systems.