Enhancement of energy storage performance of (Bi0.5Na0.5)0.7Sr0.3TiO3 ceramics by introducing La(Mg0.5Zr0.5)O3

Abstract

With the development of pulsed power devices in the direction of miniaturization, integration, and safety, the development of dielectric capacitors with large energy storage density (W_rec), high energy storage efficiency (η), and decent energy storage stability has become an important topic that needs to be discussed in depth in the academic community. In this study, (1 − x)(Bi_0.5Na_0.5)_0.7Sr_0.3TiO₃-xLa(Mg_0.5Zr_0.5)O₃ [(1 − x)BNST-xLMZ] ceramics were prepared by traditional solid-phase method. Through rational component manipulation, the introduction of LMZ effectively disrupted the long-range ordered arrangement of the original matrix, constructing short-range polar nano-microregions that consequently delayed the saturation polarization of ceramics and reduced the residual polarization. Meanwhile, the introduction of LMZ significantly affects the microstructure and relaxor behavior of BNST-based ceramics, resulting in reduced grain size and a more compact ceramic structure. It was found that 0.85BNST-0.15LMZ ceramic exhibited decent energy storage performance under an electric field of 400 kV/cm, with a large W_rec of 4.53 J/cm and high η of 87.50%. It is noted that 0.85BNST-0.15LMZ ceramics exhibited ultra-fast discharge rate of 23 ns. These results indicate that 0.85BNST-0.15LMZ ceramics have broad development prospects in the field of supercapacitors for energy storage.