A facile one-pot hydrothermal synthesis of cobalt sulfide nanospheres integrated with graphene nanocomposite as electrode material for high-performance supercapacitors

Transition metal chalcogenides have fascinating characteristics are considered as electrode materials for high-performance energy storage devices. Herein, we report the CoS/G nanocomposite was successfully synthesized by a simple one-pot hydrothermal method. The phase formation and morphology of the obtained materials were analyzed by various techniques. The electrochemical properties of the prepared electrode materials were assessed from cyclic voltammetry in a three-electrode system. The obtained cyclic voltammetry curves demonstrate pseudocapacitive behavior for prepared materials due to the synergistic effect between Cobalt and sulfur. The Galvanometric Charge Discharge (GCD) profile of the materials confirms the pseudocapacitive nature and specific capacitance calculated from these curves. The CoS/G nanocomposite delivered high specific capacitance 739.83 Fg(-1) compared to the pure CoS nanospheres 390 Fg(-1) and prolonged cyclic stability with 91.2% capacity retention after 3000 cycles. Overall, these excellent electrochemical performances indicate the CoS/G nanocomposite as a desirable electrode material for commercial supercapacitor applications.