Improvement of the energy storage performance of antiferroelectric Pb,La(Zr,Ti)O₃ thin films by the LaNiO₃ buffer layer on the metal electrode

Conductive LaNiO₃ (LNO) buffer layers are grown on silicon and Pt-covered silicon and the effects on Pb_0.94La_0.04(Zr_0.95Ti_0.05)O₃ (PLZT) thin films are studied. The PLZT films on LNO-buffered Si and LNO-buffered Pt show different preferred orientations with the film on Pt. The LNO buffer layer not only induces the columnar growth of PLZT, but also reduces the surface roughness of the PLZT films. By introducing the LNO buffer layer on Pt, the PLZT thin film can achieve high polarization while reducing the window width of the hysteresis loop. The PLZT film on LNO/Pt exhibits the best energy storage performance in all samples. The recoverable energy density (W_Rec) of 15.66 J cm⁻³ is obtained, which is 19% higher than the W_Rec of the PLZT film on LNO/Si and twice higher than the maximum W_Rec of the PLZT film on Pt. Moreover, the PLZT on LNO/Pt has an energy storage efficiency of 73% and exhibits better voltage stability. The nonlinear dielectric response results are used to analyze the different performances of the samples. This study suggests that the energy storage performance of the capacitors based on the antiferroelectric films can be further improved by adding the buffer layer on metal electrodes.