Simultaneous enhancement of energy storage performance and thermal stability of NaNbO3-based ceramics via multi-scale modulation

Abstract

More and more attention is being paid to the environmental friendliness of the dielectric capacitors, which have a rapid charging and discharging speed and steady operation. However, the low recoverable energy storage density (Wrec) limits the practical application of dielectric capacitors in solid-state energy storage devices. In this paper, (1–x) (0.92NaNbO3-0.08Bi(Mg0.5Ti0.5)O3)-xSrTiO3(x = 0.05, 0.10, 0.15, 0.20) energy storage ceramics were fabricated based on various strategies such as nanodomain engineering, component and grain size optimization. Thus excellent energy storage performance (Wrec ∼ 6.0 J/cm3, η ∼ 81.0%) was obtained in NN-BMT-0.15ST. SrTiO3 could enhance the internal disorder, improve the relaxation properties and increase the breakdown field strength of ceramics. Signifi-cantly domain relaxor behavior, as evidenced by Vogel-Fulcher (V-F) model, provides strong evidence for restraining early polarization saturation. In addition, Pulse charge/discharge tests have illustrated that the sample has excellent and stable charge/discharge performance (CD ∼ 1068.9 A/cm2, PD ∼ 96.1 MW/cm3, t0.9 ≈ 0.99 μs) It is concluded that there is a huge prospect of NN-BMT-0.15ST ceramics as a kind of pulsed-power-storing electronics.