Energy storage performance of SrSc0.5Nb0.5O3 modified (Bi,Na)TiO3-based ceramic under low electric fields

Dielectric ceramics with a high recoverable energy density (W-rec) and high efficiency are desirable for the development of pulsed power capacitors under low electric fields. In this study, through the introduction of SrSc0.5Nb0.5O3 into (Bi0.5Na0.5Ti0.95Al0.025Nb0.025O3) [(1-x)BNTA-xSSN], a considerable recoverable energy storage density (W-rec) of approximately 2.7 J/cm(3) and energy storage efficiency (eta) of approximately 76 % at 210 kV/cm are achieved at x = .1; additionally, eta is further improved to 85 % at x = .2. Moreover, eta and W-rec of .9BNTA-.1SSN exhibit outstanding stability (thermal and frequency stability) at 150 kV/cm, which is superior to that of other lead-free ceramics. The excellent energy storage performance is attributed to the increased relaxation degree and the formation of ferroelectric nanodomains, whereas the enhanced E-b is ascribed to the increased electrical resistivity and decreased grain size upon modification. These results indicate the potential of (1-x)BNTA-xSSN as an ideal candidate for energy-storage applications.