Enhanced performance of hierarchical CuS clusters applying TRGO as conductive carrier for supercapacitors

A facile hydrothermal-assisted process without surfactant was developed to prepare hierarchical CuS clusters and novel CuS-thermal reduced graphene oxide (TRGO) composites as advanced electrodes. The preparation of TRGO was simple and efficient without protective atmosphere and reagent, and the CuS-TRGO composites were characterized by distributed CuS microspheres coated with TRGO carrier uniformly to improve the pseudocapacitance properties. Electrochemical performance of the electrode of CuS-TRGO composites was elucidated by utilizing cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy methods respectively. The electrode exhibited ultrahigh specific capacitance up to 1222.5Fg(-1) at 1 Ag-1, good rate capability as well as excellent cycling stability with 92.11% capacitance retention after 3000 charge-discharge cycles at 5Ag(-1), which implied that the as-prepared CuS-TRGO could be a favorable and suitable electrode material as supercapacitors in energy storage.