Improved Dielectric and Energy Storage Properties of Ba0.8Ca0.2TiO3 Ceramics by Doping Ba(Mg1/3Nb2/3)O3.

Lead‐free Ba0.8Ca0.2TiO3–xmol%Ba(Mg1/3Nb2/3)O3 (abbreviated as BCT20–xBMN, x = 0–8) ceramics are fabricated by a conventional solid‐state reaction method. All BCT20–xBMN ceramics have pure perovskite phases which gradually change from tetragonal phase to cubic phase. The average grain size decreases significantly from ≈23 to ≈1.2 μm with the increase in BMN content. The Tm corresponding to the dielectric maximum of BCT20–xBMN decreases with the increase in x, and the room temperature dielectric constant increases significantly. The recoverable energy storage density Wrec and efficiency η% are enhanced to 0.17 J cm−3 and 81.3% for BCT20–6BMN due to the reduced remanent polarization by BMN doping. The Wrec increases with increasing temperature and shows peak values near the Tm. The η% of BCT20–6BMN and BCT20–7BMN has good temperature stability due to enhanced relaxor behavior. [ABSTRACT FROM AUTHOR]