Simultaneously realizing high energy density and high efficiency in NaNbO3-BaTiO3-based ceramic capacitors

Dielectric capacitors, which can achieve tremendous power density and ultrafast charge/discharge speed, are crucial components for high power equipment. Yet, the synchronous achievement in high recoverable energy density (Wrec) and high efficiency (eta) is a long-term difficulty for dielectric ceramics. Herein, the (0.85 - x)NaNbO3-0.15BaTiO(3)-xBi(Mg1/3Ta2/3)O-3 (NN-BT-xBMT) relaxor ferroelectric ceramics were proposed and studied. The doping of BMT was conducive to promoting the microstructure and bandgap and improving the dielectric relaxation properties of NN-BT ceramics. Finally, the sample of x = 0.10 presented a high Wrec of 5.9 J/cm3 and a high eta of 90% simultaneously. In addition, the sample also exhibited superb charge/discharge performances with large power density (PD = 137 MW/cm(3)) and fast charge/discharge speed (t0.9 = 39 ns). The above results reveal that the NaNbO3-based ceramics could serve as potential alternatives for advanced dielectric capacitors.