Synthesis and electrochemical properties of Fe3O4/MnO2/RGOs sandwich-like nano-superstructures

The Fe3O4/MnO2/RGOs (Reduced graphene oxide) sandwich-like nano-superstructures reported in this article were fabricated by using an eco-friendly mechanical stirring route at room temperature without any catalysts or templates. In this nano-superstructure, three-dimensional (3D) hierarchical MnO2 shell was assembled by two-dimensional (2D) nanoplates and Fe3O4/MnO2 core-shell was coated by RGO layers. The sandwich-like nano-superstructures show better electrochemical performance comparing to the pure MnO2 and Fe3O4/MnO2 nanoparticles. The maximum specific capacitance can reach 77.5 F/g at the current density of 0.5 A/g and maintain 35.0 F/g (55% of SC at 0.5 A/g) at the current density of 20 A/g. It was found that the electrocapacitive performances of the Fe3O4/MnO2/RGO electrodes are highly affected by the connection effectiveness between Fe3O4/MnO2 particles and graphene layers.