Enhanced energy storage performance of (Ba0.85Ca0.15) (Zr0.10Ti0.90) O3-based ceramics through a synergistic optimization strategy

(Ba0.85Ca0.15)(Zr0.10Ti0.90)O3 (BCZT) ceramics exhibit excellent electrical properties due to the existence of morphotropic phase boundary (MPB), and have received extensive attention and research. However, its energy storage density is relatively unsatisfactory. In this work, we propose a synergistic optimization strategy to improve the energy storage performance of BCZT, namely, the introduction of Sr0.7La0.2TiO3 (SLT) and the sintering aid of lithium carbonate. The former can hinder the long-range ferroelectric order, induce polar nanodomains, and improve energy storage efficiency. The latter can reduce the sintering temperature and promote the densification of grains, which is beneficial to improve the energy storage density. The results show that the addition of SLT widens the dielectric peak, and the Curie temperature moves to a lower direction. The ceramics have good frequency stability. Under the electric field of 200 kV/cm, it shows the highest energy storage density (1.031 J/cm3) and the energy storage efficiency is 59.8%. After the introduction of lithium carbonate into the 0.8BCZT-0.2SLT ceramics, the sintering temperature is reduced by about 80 °C. Scanning electron microscopy results show that all samples have dense microstructures. In 0.8BCZT-0.2SLT-2wt% Li2CO3 ceramics, the obtained maximum recoverable energy storage density is 1.436 J/cm3, and the efficiency is 56.7%.