Enhanced electrical energy storage properties in La-doped (Bi0.5Na0.5)0.93Ba0.07TiO3 lead-free ceramics by addition of La2O3 and La(NO3)3

Abstract

Lead-free [(Bi0.5Na0.5)0.93Ba0.07]1−x La x TiO3 (BNBLT) ceramics for energy storage application were prepared by traditional solid-state reaction technique, and the La3+ ions doping content was varied at 0 ≤ x ≤ 0.04. The BNBLT ceramics showed single-phase perovskite structure without impurity phase. Compact and uniform microstructure with fine grain size was obtained. The remanent polarization and coercive field decreased with the increase in La3+ ions doping content, and the energy storage density increased drastically. The maximum energy storage density of the BNBLT ceramics at x = 0.04 was 1.09 J/cm3 by using La2O3 powders and can be further increased to 1.21 J/cm3 using La(NO3)3 powders, and meanwhile, the breakdown field strength increased obviously. Anti-ferroelectric-like behavior with a double pinched P–E hysteresis loop was observed in La3+-doped BNBLT ceramics at room temperature, which is promising candidate for energy storage dielectric ceramic.