Reduced graphene oxide-coated mulberry-shaped α-Fe2O3 nanoparticles composite as high performance electrode material for supercapacitors

We report a facile method to synthesize nanocomposites with Fe2O3 nanoparticles (NPs) loaded on the surface of the reduced graphene oxide nanosheets (rGO) or wrapped into rGO sheets by simply regulating the temperatures and times of the hydrothermal reaction, which combines the growth of Fe2O3 NPs and the reduction of graphene oxide simultaneously. The morphology and microstructure of these samples were examined by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectra, X-ray photoelectron spectroscopy, Fourier transform infrared spectrometer and nitrogen isothermal adsorption-desorption. The effects of different temperatures and times of hydrothermal reaction on the microstructure and capacitive performance of these prepared composites were investigated in detail. The as-synthesized mulberry-shaped α-Fe2O3 NPs/graphene nanocomposite shows remarkable pseudocapacitive activity containing high specific capacitance (1051 F g−1 at 1 A g−1) and excellent rate capability (548 F g−1 at 30 A g−1).