Enhanced energy storage and fast charge-discharge capability in Ca0.5Sr0.5TiO3-based linear dielectric ceramic

Ca0.5Sr0.5(TaxTi1-1.25x)O-3-2 wt%SiO2 ceramic samples were fabricated by solid state method. XRD data showed all samples are assigned to perovskite structure, dense microstructure and relatively large grain size were displayed by SEM. Moreover, the effect of Ta5+ ion doping on increased resistivity and energy barrier height were analysed by impendance spectra. Exceptional energy storage performances which are 2 J/cm(3) in energy density and 96% in energy efficiency under breakdown strength of 360 kV/cm can be obtained in the sample with x = 0.024, also possessing over 80% efficiency in a wide range of temperature (20-120 degrees C). Additionally, pulsed charging and discharging tests were carried out aiming to evaluate the practical performance of ceramic materials. The prominent parameters I-max of 32.2 A, C-D of 256.1 A/cm(2), P-D of 15.4 MW/cm(3) and outstanding temperature stability (20-120 degrees C) were achieved in the sample with x= 0.024 as well, releasing stored energy sharply (t(0.9) < 25 ns). These properties verified this lead-free linear dielectric ceramic can be promising candidate for wider applications in the fields of energy-storage and charge-discharge. (C) 2019 Elsevier B.V. All rights reserved.