Enhanced energy storage performance of Ba0.94(Bi0.5K0.5)0.06Ti0.85Zr0.15O3 relaxor ceramics by two-step sintering method

Abstract A series of Ba0.94(Bi0.5K0.5)0.06Ti0.85Zr0.15O3 (referred to as BBK) ceramics with high density microstructure were fabricated by a two-step sintering method. A strong influence of the sintering temperature on the microstructure, dielectric properties and relaxor behavior of BBK ceramics was observed. Slim hysteresis loops could be obtained in all BBK ceramics, and the optimal sample sintered at 1250 °C for 6 h shows a high dielectric constant (er ˜3066 at 102 Hz), a low dielectric loss (tan δ ˜0.005 at 102 Hz), a high energy density (Wdischarge ˜0.95 J/cm3 at 76 kV/cm) and a high energy efficiency (η ˜88% at 76 kV/cm). The correlation of electrical properties for BBK ceramics with sintering temperatures could be attributed to grain size effect and relaxor behavior.