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)(0.94)Ba0.06Ti1-x(Al0.5Nb0.5)(x)O-3 (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/cm(3). The temperature dependence of dielectric constant epsilon(r) and dielectric loss tan delta 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. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.