Electrochemical battery-type supercapacitor based on chemosynthesized Cu2S[sbnd]Ag2S composite electrode

Abstract

Metal sulfide-based electrochemical supercapacitors are widely attracted owing to their high electrical conductivity and excellent redox properties. Moreover, the fabrication of high performance supercapacitors based on simple and cost effective chemical routes is in strong demand. In this study, a facile and low cost, successive ionic layer adsorption and reaction (SILAR) technique is used to form a Cu2SAg2S composite electrode on nickel foam in a common sulfur source beaker for both copper and silver with less time and material consumption. The electrodes exhibits a high specific capacity of 772 Cg−1 at a scan rate of 10 mVs−1 compared to pristine Cu2S and Ag2S and shows excellent cycling stability with a capacity retention of 89% after 2000 CV cycles. This is attributed to the highly conductive and reactive Ag2S layer, which simplifies the diffusion of electrolyte ions to access active Cu2S materials and facilitates rapid electron transport to achieve high-performance battery-type supercapacitors. This study provides a simple and cost-effective approach to the fabrication of high-performance battery-type supercapacitors based on highly conductive and earth-abundant, copper-based composite metal sulfide electrodes.