Fe₂O₃/Reduced Graphene Oxide/Fe₃O₄ Composite in Situ Grown on Fe Foil for High-Performance Supercapacitors

A Fe₂O₃/reduced graphene oxide (RGO)/Fe₃O₄ nanocomposite in situ grown on Fe foil was synthesized via a simple one-step hydrothermal growth process, where the iron foil served as support, reductant of graphene oxide, Fe source of Fe₃O₄, and also the current collector of the electrode. When it directly acted as the electrode of a supercapacitor, as-synthesized Fe₂O₃/RGO/Fe₃O₄@Fe exhibited excellent electrochemical performance with a high capability of 337.5 mF/cm² at 20 mA/cm² and a superior cyclability with 2.3% capacity loss from the 600th to the 2000th cycle.