High energy storage performance of (Na0.5Bi0.5)TiO3 thin film induced by stress engineering
Yichen Li, Yao Yao, L. Zhou, Jing Wang, Lei Zhao
Abstract
Relaxor ferroelectrics are the primary candidates for high-performance energy storage dielectric capacitors. Here, stress engineering, which was realized by optimizing the lattice mismatch between (Na 0.5 Bi 0.5 )TiO 3 film and SrRuO 3 /(La 0.5 Sr 0.5 )CoO 3 bottom electrodes, was used to enhance the energy storage performance of (Na 0.5 Bi 0.5 )TiO 3 relaxor ferroelectric film. As a result, in-plane compressive stress caused by the lattice mismatch between (Na 0.5 Bi 0.5 )TiO 3 film and (La 0.5 Sr 0.5 )CoO 3 bottom electrode leads to a large W rec of 45.7 J/cm 3 with η of 79.4% at 2000 kV/cm in (Na 0.5 Bi 0.5 )TiO 3 film, which is 54.4% higher than that of (Na 0.5 Bi 0.5 )TiO 3 film with in-plane tensile stress. In addition, the W rec of (Na 0.5 Bi 0.5 )TiO 3 film with in-plane compressive stress shows good thermal stability and frequency stability with variations of 5.8% at 30–120 °C and 6.9% at 0.2–20.0 kHz. This work may provide some new perspectives for the design of dielectric capacitors with high energy storage performance. • Stress engineering is realized in NBT relaxor ferroelectric films. • The in-plane compressive stress contributes to increased polarization in NBT film. • W rec and η reach 45.7 J/cm 3 and 79.4 % in NBT@LSCO films. • W rec and η of NBT@LSCO films have good thermal stability and frequency stability.