Development of Cobalt Sulfide-graphene Composite for Supercapacitor Applications

Co9S8/reduced graphene (CSRG) has been prepared by a facile two step hydrothermal method and used as a supercapacitor electrode material. It is anticipated that the Co9S8 and reduced graphene oxide (RGO) would serve as a spacer material to each other to stop the agglomeration and simultaneous contribution of electrical double layer capacitance (RGO) and pseudocapacitance (Co9S8) would provide high electrochemical properties. The chemical analysis has been done by Fourier transform infrared spectroscopy and the morphology is characterised by field emission scanning electron microscopy. CSRG shows a high electrical conductivity of 98 S m(-1). The symmetric supercapacitor shows a specific capacitance of similar to 728 F g(-1) with a current density of 2 A g(-1). CSRG also showed an energy density of 25.2 Wh kg(-1) with a power density of 1000 W kg(-1).