The enhanced electrical energy storage properties of (Bi 0.5 Na 0.5 )TiO 3 –BaTiO 3 /graphene oxide heterogeneous structures

Heterogeneous structures of lead-free 0.94(Bi 0.5 Na 0.5 )TiO 3 –0.06BaTiO 3 solid-solution thin film and few-layer graphene oxide (GO) are prepared by using Langmuir–Blodgett (L–B) method, and their morphology, piezoelectric properties and electrical energy storage performances are investigated. It is found that the electrical breakdown strength of solid-solution thin film is significantly improved due to the covalently bonded GO nanosheets, resulting in the present of local fields that could be counteractive to the applied electric field. The heterostructures possess an outstanding electrical energy storage density as high as 4.26 J cm −3 at elevated temperatures (80–120 °C). The results demonstrate that the development of dielectrics-GO heterostructures is an effective approach in enhancing the energy storage density of dielectric capacitors for their practical applications.