Solvothermally induced α-Fe2O3/graphene nanocomposites with ultrahigh capacitance and excellent rate capability for supercapacitors

Abstract

Well crystallized Fe₂O₃ with the particle size mainly concentrated around 35–40 nm combined with graphene is fabricated under solvothermal conditions. The optimized Fe₂O₃/GH-2 composite sample possessing 49.7 wt% Fe₂O₃ has a high specific BET surface area of 215.3 m² g⁻¹. When used as a supercapacitor electrode, the capacitances are admirable 2310 F g⁻¹ at 5 mV s⁻¹ and 615 F g⁻¹ at an amazingly high current density of 100 A g⁻¹. When used as an anode material for asymmetric hybrid capacitors, the composite shows a promising future for energy storage with high energy density, high power density and excellent cycle life.