Development of carbon-based copper sulfide nanocomposites for high energy supercapacitor applications: A comprehensive review

•Nanomaterials based on CuS and its composites are summarized for supercapacitor applications.•Role of electrolytes on the electrochemical properties has been discussed.•CuS nanotubes (NTs) have achieved the capacitance of 2393 F/g in polysulfide electrolyte.•Acetylene black/CuS nanosheets composite exhibited ultrahigh capacitance of 2981 F/g at 1 A/g current density.•Future perspectives and challenges for enhancing the charge storage capabilities are highlighted. The present paper reports comprehensive reviews of the recent development in carbon material with reliance on carbon-based copper sulfide nanocomposites and their high energy supercapacitor applications. Due to their exceptional features, among various transition metal sulfides, copper sulfides (CuxS, x = 1–2) have sparked a lot of interest in energy storage systems and have long been acknowledged as major industrial materials with a variety of purposes in sectors as diverse as electronics, photovoltaics, catalysis, sensors, and energy storage. Owing to its promising electrochemical performance, simplicity of accessibility, high electrical conductivity, low electronegativity, distinctive crystal shapes, high specific capacity, strong redox activity, and cheap manufacturing costs have sparked intense interest in the development of growing supercapacitors to fulfill the skyrocketing demand for efficient electrochemical energy storage devices. As a supercapacitor electrode material, several composites of copper sulfide with varied carbon-based systems such as carbon nanotubes, graphene, and activated carbon have been briefly mentioned here. Furthermore, this study describes the existing problems as well as some potential approaches that may encourage the superior strategic design of smarter carbon-based copper sulfide nanomaterials for the next-generation high energy supercapacitors applications. The current problems and potential advancements in this area for establishing energy storage devices that are efficient are also reviewed. [Display omitted]