Functional carbons for energy applications.

• The critical role of carbons, including biomass-based carbon materials and their importance, highlighted. • Role of carbons and their function in batteries, supercapacitor, and Fuel cells were described. • Various strategies for boosting energy devices' performance via conductive materials are reviewed. • Several commercially available carbon-based energy systems were presented. • The current challenges and future possibilities are discussed. In recent years, several innovations and studies have been remarked to develop carbon-based nanocomposites and their applications. Carbon-based materials have received increased attention in every category, including the energy sector, water purification, and biomedical. Besides, carbon and its derivatives are well-known for their remarkable features such as high conductivity, surface area, excellent chemical, and mechanical stability. On the other hand, transitional metal oxides (TMO) and conducting polymers (CPs) are renowned for their docility, low price, and reliable performance. In general, the carbon electrodes functioning was reported to improve considerably by homogeneous blending of TMO and CPs. This approach results in developing excellent electrode material that can deliver high-performance functional composites for electrochemical energy storage systems. In this review, we discussed the synergistic effect and the resulting performance of functional carbons considering features like morphology, surface area, and other parameters that influence the activity of functional carbons and their electrochemical studies. [Display omitted] [ABSTRACT FROM AUTHOR]