Large enhancement of energy storage density in (Pb0.92La0.08)(Zr0.65Ti0.35)O3/PbZrO3 multilayer thin film

(Pb0.92La0.08)(Zr0.65Ti0.35)O3 (PLZT), PbZrO3 (PZO) films, and type A and type B PLZT/PZO multilayer thin films were deposited on Pt(111)/TiOx/SiO2/Si substrates by sol-gel method, where type A and type B films stand for PLZT/PZO/PLZT/PZO/PLZT/PZO and PLZT/PZO/PLZT/PLZT/PZO/PLZT multilayer thin film, respectively. Compared to the PLZT and PZO film, enhanced breakdown field strength and improved energy storage density were obtained in type A and B multilayer thin films. A superior energy storage density of 29.7 J/cm3 with the energy storage efficiency of 50.8% was achieved in type B multilayer thin film, corresponding to 81% enhancement compared with the energy storage density of PLZT films (16.4 J/cm3). Additionally, the type B multilayer thin film exhibits a good thermal stability up to 160 °C and excellent fatigue endurance after 107 charging-discharging cycles. The enhanced energy storage performance of type B multilayer thin film shows promise and may stimulate further researches on energy storage applications of multilayer dielectric thin films.