Outstanding comprehensive energy storage performance in lead-free BiFeO3-based relaxor ferroelectric ceramics by multiple optimization design.

Lead-free ceramic-based dielectric capacitors with high-performance energy storage properties have become an emerging issue recently as a result of the applications in high-power and/or pulsed-power technologies. However, the trade-off between various parameters, such as maximum polarization P max , remnant polarization P r and dielectric breakdown strength E b , restricts the further improvement of the energy storage properties of dielectric ceramics. Herein, a synergistic optimization strategy via simultaneous enhancement of P max and E b and reduction of P r is adopted to achieve outstanding energy storage properties for Bi 0.9 La 0.1 FeO 3 -Ba 0.7 Sr 0.3 TiO 3 NaNb 0.85 Ta 0.15 O 3 relaxor ferroelectric ceramics, characterized by an ultrahigh recoverable energy density W rec of 15.9 J/cm3 and high efficiency η of 87.7%. The inborn gene of BiFeO 3 -based materials results in high P max and the improved relaxor behavior gives rise to a small P r value. In Particular, a very large value for E b is obtained by tailoring multiple intrinsic and extrinsic factors. These results demonstrate the reliability and feasibility of the multiple optimization strategy proposed in this work to develop novel dielectric ceramics for advanced energy storage applications. [Display omitted] [ABSTRACT FROM AUTHOR]