The effect of deposition time on the morphology of CuS electrodes fabricated by chemical bath deposition for supercapacitor applications

This paper presents the synthesis of copper sulfide (CuS) electrode utilizing chemical bath deposition (CBD) and the study of the effect of complexing agent on the morphology of CuS electrode. The aim of this study is to find the ideal time for the synthesis of CuS and to find the capacitance and highest potential of the CuS electrode synthesized at the ideal time. In this project, CuS solution is formed using copper (II) sulphate (CuSO4) solution, thioacetamide solution, and a complexing agent which is citric acid. Homogeneous ultrathin nanospheres of CuS thin films have been successfully developed on nickel foam (NF) by simple and low-cost CBD method which is a promising electrode material for high-performance supercapacitors. The CBD process was carried out at different time intervals which are 30, 60, 90 and 120 min to find the ideal deposition time for CuS/NF electrode fabrication. The surface morphological analysis showed uniform growth of CuS nanospheres on NF surface. Structural analysis confirms the formation of hexagonal crystal structure of CuS. The electrochemical performances were tested by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance techniques. The best capacitance that was recorded by CuS fabricated at 60 min with a specific capacitance of 615 F/g at 1 A/g current density. Hence, the ideal deposition time of CuS/NF electrode fabrication for high supercapacitor performance is 60 min. The encouraging results suggest that CuS nanoflakes prepared by chemical bath deposition can serve as promising electrode materials for high performance supercapacitors in the future.