The grain size and domain structure synergistic effect on BNT based lead-free ceramics with high energy storage properties

Ceramic capacitors having great energy-storage performance (ESP) are receiving more and more concern in the electronics industry. In this paper, high ESP is obtained in 0.6Bi 0.5 Na 0.5 TiO 3 –0.4Bi 0.2 Sr 0.7 TiO 3 (BNT-BST)-based samples through doping the Sr(Sc 0.5 Nb 0.5 )O 3 (SSN) component. The results show that the recoverable energy density ( W rec ) and efficiency ( η ) of the materials will be significantly improved by adjusting the relaxation characteristics and domain structure engineering. In addition, the breakdown filed of ceramics is also improved by inhibition grain growth. The BNT-BST-0.15SSN ceramic has achieved high comprehensive ESP ( W rec  = 5.49 J/cm 3 , η  = 93.6 %) at an electric field of 455 kV/cm. Meanwhile, the ceramic shows outstanding temperature (25–160 °C), frequency (1–500 Hz) and cycle (1–10 4 ) stability (the variation of W rec / η  < 5 %). Therefore, the BNT-BST-0.15SSN ceramic is expected to be a suitable candidate of environmentally friendly materials as advanced pulsed capacitor application.