Enhanced energy storage properties and good stability of novel (1–x)Na0.5Bi0.5TiO3–xCa(Mg1/3Nb2/3)O3 relaxor ferroelectric ceramics prepared by chemical modification

The increase in energy consumption and its collateral damage on the environment has encouraged the development of environment-friendly ceramic materials with good energy storage properties. In this work, (1– x )Na 0.5 Bi 0.5 TiO 3 - x Ca(Mg 1/3 Nb 2/3 )O 3 ceramics were synthesized by the solid-state reaction method. The 0.88Na 0.5 Bi 0.5 TiO 3 -0.12Ca(Mg 1/3 Nb 2/3 )O 3 ceramic exhibited a high recoverable energy storage density of 8.1 J/cm 3 and energy storage efficiency of 82.4% at 550 kV/cm. The introduction of Ca(Mg 1/3 Nb 2/3 )O 3 reduced the grain size and increased the band gap, thereby enhancing the breakdown field strength of the ceramic materials. The method also resulted in good temperature stability (20–140 °C), frequency stability (1–200 Hz), and fatigue stability over 10 6 cycles. In addition, an ultrahigh power density of 187 MW/cm 3 and a fast charge-discharge rate ( t 0.9  = 57.2 ns) can be obtained simultaneously. Finite element method analysis revealed that the decrease of grain size was beneficial to the increase of breakdown field strength. Therefore, the 0.88Na 0.5 Bi 0.5 TiO 3 -0.12Ca(Mg 1/3 Nb 2/3 )O 3 ceramics resulted in high energy storage properties with good stability and were promising environment-friendly materials for advanced pulsed power systems applications.