▎ 摘　　要

Although there have been many studies on asymmetric supercapacitors (ASCs), anode materials are still mainly carbon-based. However, carbon-based materials with low specific capacitance cannot match the cathode materials, limiting the energy density of ASCs. In this research, a low-cost and environmentally friendly anode of homogeneous alpha-Fe2O3 nanoparticles grown on three-dimensional graphene (3DG) hydrogel is synthesized, with significant specific capacitance (788.6 F g(-1) at 1 A g(-1)) and exceptionally good stability (retaining 82.3% capacitance after 5000 cycles). The composite material of NiCo2O4 nanorods grown on 3DG (NiCo2O4/3DG) has been prepared as the cathode by a similar method. The NiCo2O4/3DG also shows excellent electrochemical performance (1264.3 F g(-1) at 1 A g(-1) and stability of 91.7% after 5000 cycles). Furthermore, the ASCs of NiCo2O4/3DG//alpha-Fe2O3/3DG, which is composed of the as-prepared cathode and anode materials, exhibits excellent energy density of 77.8 W h kg(-1) at a power density of 800 W kg(-1), and outstanding stability of 81.6% after 5000 cycles at 10 A g(-1). Therefore, this proves that alpha-Fe2O3/3DG is a promising anode material for supercapacitors.