Decorating reduced graphene oxide with Co3O4 hollow spheres and their application in supercapacitor materials

• Co3O4 hollow spheres/graphene composite has been synthesized by solvothermal method.
• The Co3O4 hollow spheres with good purity and homogenous size are absorbed onto the graphene.
• The Co3O4/RGO composite has potential application as electrode materials.

In this paper, a composite of reduced graphene oxide decorated by Co3O4 hollow spheres (Co3O4/RGO composite) has been synthesized by a one-pot solvothermal method. The samples are characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR), Raman spectra and so on. The results demonstrate that the Co3O4 hollow spheres with good purity and homogenous size are absorbed onto the reduced graphene oxide sheets as spacers to prevent the aggregation of the graphene oxide sheets. Furthermore, the well electrochemical properties demonstrate that the Co3O4/RGO composite might have potential applications as electrode materials for supercapacitors.