Fabrication of Metal Sulfides/Graphene Nanocomposites for the Applications in Supercapacitors. Part I: NiS/Graphene

NiS/reduced graphene oxide nanocomposites were prepared by a hydrothermal method. Electron microscope observation revealed that the materials were of thin sheet-like structure and X-ray diffraction indicated the NiS of high-purity on the graphene nanosheets. Nitrogen adsorption on the samples at 77 K revealed the porous properties. Such materials were pseudo-active, exhibiting high specific capacitance of 978 F g-1 at 1 A g-1 in 3M KOH and high capacitance retention of 76% over 1000 cycles at 5 A g-1, promising for applications in supercapacitors.