Abstract
Flexible thin-film capacitors have gained a lot of attention in energy storage applications because of their high energy storage densities and efficient charge-discharge performances. Among these materials, antiferroelectric compounds with low residual polarization and strong saturation polarization have shown great promise. However, their comparatively low breakdown strength continues to be a major issue restricting further developments in their energy storage performance. While La(3+) doping has been explored as a means to enhance the energy storage capabilities of antiferroelectric thin films, the specific influence of La(3+) on breakdown strength and the underlying mechanism of phase transitions have not been thoroughly investigated in existing research. In this study, Pb(1-3x/2)La(x)ZrO(3) thin films were successfully synthesized and deposited on mica substrates via the sol-gel process. By varying the concentration of La(3+) ions, a detailed examination of the films' microstructures, electrical properties, and energy storage performances was carried out to better understand how La(3+) doping influences both breakdown strength and energy storage characteristics. The results show that doping with La(3+) significantly improves the breakdown strength of the films, reduces the critical phase transition electric field (E(F)-E(A)), and enhances their energy storage capabilities. Notably, the Pb(0.91)La(0.06)ZrO(3) thin film achieved an impressive energy storage density of 34.9 J/cm(3) with an efficiency of 58.3%, and at the maximum electric field strength of 1541 kV/cm, the recoverable energy density (W(rec)) was 385% greater than that of the PbZrO(3) film. Additionally, the film still maintains good energy storage performance after 10(7) cycles and 10(4) bending cycles. These findings highlight the potential of flexible antiferroelectric Pb(0.91)La(0.06)ZrO(3) thin films for future energy storage applications.