Improving energy storage properties in (Ba0.75Sr0.1Bi0.1)(Ti0.9Zr0.1)O3 ceramic thick films by adding (Sb0.5Li0.5)TiO3, domain engineering and defect engineering

Abstract

(1-x)(Ba_0.75Sr_0.1Bi_0.1)(Ti_0.9Zr_0.1)O₃-x(Sb_0.5Li_0.5)TiO₃ (BSBiTZ-xSLT, x = 0.025, 0.05, 0.075, 0.1) ceramic thick films were prepared via film scaping process. The decrease of tetragonal, rhombohedral and orthogonal phases and the appearance of cubic phase in the BSBiTZ-xSLT ceramic thick films strengthen the ferroelectricity and weaken the relaxation characteristic with the increase of SLT doping amount. For the BSBiTZ-0.025SLT ceramic thick film, fine grain size of 0.86 μm, excellent uniformity of grain distribution, low porosity, larger bandgap of 2.44 eV and grain boundary resistance of 153 kΩ reinforce the breakdown field up to 350 kV/cm. Doping SLT, domain engineering and defect engineering successfully reduce the remnant polarization and improve the relaxation ferroelectric characteristic with the obvious frequency dispersion, wide peak of the dielectric constant extending to ∼120 °C with fluctuation <10 %, and low dielectric loss of <0.1. In the BSBiTZ-0.025SLT ceramic thick film, the highest recoverable energy storage density (W_rec = 1.92 J/cm³), larger energy storage efficiency (η = 88.32 %), pulse energy storage performance (W_d = 1.48 J/cm³), current density (C_D = 743.09 A/cm²) and power density (P_D = 130.04 MW/cm³) are achieved under 350 kV/cm. The excellent energy storage performance combined with the excellent temperature stability and fatigue resistance provide the good development prospect as a lead-free BT-based ceramic dielectric capacitor in high-power pulse energy storage system.