Effect of introducing Sr2+/Hf4+ on phase structures, bandgaps, and energy storage performance in Bi0.47Na0.47Ba0.06TiO3-based ferroelectric ceramic
Junlin Wu, Qin Feng, Chaoying Luo, Tianhui Shi, Zhenyong Cen, Xiyong Chen, Changlai Yuan, Toyohisa Fujita, Nengneng Luo
Abstract
Dielectric energy storage ceramic capacitors have garnered wide attraction in recent years due to their splendid integrated energy storage properties. However, difficulties in obtaining splendid integrated properties limit their industrial application. This work achieved splendid integrated energy storage properties by doping Sr 2+ /Hf 4+ into the Bi 0.47 Na 0.47 Ba 0.06 TiO 3 ceramics. The R 3 c and P 4 bm phases were simultaneously induced and the short-range ordered polar nanoregions were formed, thereby generating a large polarization D-value by maintaining the large maximum polarization of the Bi 0.47 Na 0.47 Ba 0.06 TiO 3 ceramics and greatly reducing the remnant polarization. By increasing both the density of the grain boundaries and the difficulty of electrons leaping out of the valence band to the conduction band, the breakdown electric fields of the ceramics were greatly improved. Eventually, a high W rec of 5.83 J/cm 3 , a moderate η of 83.67%, a stable frequency ( W rec ≈ 2.84 ± 2.1% J/cm 3 , η ≈ 80.7 ± 2.8%, 1–200 Hz), excellent temperature stability ( W rec ≈ 2.89 ± 1.4% J/cm 3 , η ≈ 83.7 ± 1.0%, 20–140 °C), and a fast discharge rate (8 μs) were simultaneously obtained in the 0.8Bi 0.47 Na 0.47 Ba 0.06 TiO 3 -0.2SrHfO 3 relaxor ferroelectric ceramics . These results suggested that the co-doping of A/B sites could significantly improve the energy storage properties of the Bi 0.47 Na 0.47 Ba 0.06 TiO 3 ceramics. Furthermore, the excellent integrated properties indicate that the 0.8Bi 0.47 Na 0.47 Ba 0.06 TiO 3 -0.2SrHfO 3 ceramics are expected to meet the application requirements of dielectric capacitors under complex conditions in the future.