High energy storage properties and dielectric behavior of (Bi0.5Na0.5)0.94Ba0.06Ti1−x(Al0.5Nb0.5)xO3 lead-free ferroelectric ceramics

The influence of B-site (Al0.5Nb0.5)4+ complex-ion substitution on the phase transition, microstructure, dielectric, ferroelectric, and energy storage properties of (Bi0.5Na0.5)0.94Ba0.06Ti1−x(Al0.5Nb0.5)xO3 (BNBT-xAN) ceramics was systematically investigated. BNBT-xAN ceramics showed single-phase perovskite structure without an obvious phase transition after adding AN. Compact and uniform microstructure with almost the same grain morphology and size was obtained. The AN doping produced slimmer P–E loops and thus improved energy storage property. At the composition of x=0.04 and electric field of 70 kV/cm, the energy storage density achieved the optimum value of 0.70 J/cm3. The temperature dependence of dielectric constant εr and dielectric loss tanδ illustrated a noticeable diffuse phase transition characteristics in BNBT-xAN ceramics. These results indicated that the BNBT-AN system may be a promising lead-free material for high energy storage density capacitor.