An investigation of the dielectric energy storage performance of Bi(Mg2/3Nb1/3)O3-modifed BaTiO3 Pb-free bulk ceramics with improved temperature/frequency stability

In order to fabricate high performance dielectric capacitors for pulsed power applications, dense and homogenous Bi(Mg2/3Nb1/3)O-3-modifed BaTiO3-based Pb-free relaxor ferroelectric ceramics were obtained through a isostatic pressing technique at room temperature. Obvious relaxor behavior with a high diffusion degree is confirmed by broad and frequency-dependent dielectric peaks in 0.875BaTiO(3)-0.125Bi(Mg2/3Nb1/3)O-3 (BT-0.125BMN). Good energy storage properties including a high recoverable energy density of similar to 1.89 J/cm(3), an relatively high efficiency of similar to 83%, good dielectric/temperature/frequency dependent stability and also fatigue resistance are achieved in this composition at a high electric field of 240 kV/cm, together with a fast discharging speed of < 160 nm and high maximum current density of 503.46 A/cm(2) and a large power density of 25.12 MW/cm(3). These properties indicate that BT-0.125BMN is a promising candidate of capacitors for the pulsed power applications.