Interlayer coupling to enhance the energy storage performance of Na_0.5Bi_0.5TiO₃–SrTiO₃ multilayer films with the electric field amplifying effect

High energy storage density and good thermal stability are simultaneously achieved in a new lead-free relaxor ferroelectric 0.7Na0.5Bi0.5TiO3–0.3SrTiO3/0.6SrTiO3–0.4Na0.5Bi0.5TiO3 multilayer film.