Enhanced energy storage density by inducing defect dipoles in lead free relaxor ferroelectric BaTiO3-based ceramics

In this work, Mn-doped 0.9BaTiO3-0.1Bi(Mg2/3Nb1/3)O3 ceramics were prepared by the conventional solid state reaction method, and the effect of defect dipoles on energy storage properties of lead free relaxor ferroelectric BaTiO3-based ceramics was studied. The crystal structure, dielectric properties, and energy storage properties were explored in detail. It was found that polarization hysteresis (P-E) loops of 0.9BaTiO3-0.1Bi(Mg2/3Nb1/3)O3-x wt. % MnCO3 (0.2–0.5) ceramics took on high maximum polarization (Pmax ) and low remanent polarization (Pr ). Meanwhile, recoverable energy density (Wrec ) and energy conversion efficiency (η) were obviously enhanced by inducing defect dipoles into BaTiO3-Bi(Mg2/3Nb1/3)O3 relaxor ferroelectrics. The 0.9BaTiO3-0.1Bi(Mg2/3Nb1/3)O3-0.3 wt. % MnCO3 ceramic was found to exhibit good energy storage properties with a Wrec of about 1.70 J/cm3 and a η ∼ 90% under an electric field of 210 kV/cm. The breakdown electric field and Wrec of BaTiO3-based materials were significantly increased in the present work, and they might be good candidates for high power energy storage applications.