Nanocarbon-based electrode materials applied for supercapacitors

As one of the promising energy storage and conversion systems, supercapacitors (SCs) are highly favored owing to their high power density and good service life. Among all the key components of supercapacitor devices, the design and investigation of electrode materials play an essential role in determining the whole electrochemical charge storage performance. Recently, nanocarbon-based materials (e.g., graphene, carbon dots, graphene quantum dots, etc.) have been widely used as SC electrode materials because of their good physical structure and chemical properties, providing a new route to further improve the energy density and life span of SCs. Here, we review the latest progress of nanocarbon-based materials (including nanocarbon and nanocarbon-based composite materials) as electrode materials in SCs application. The recent progress of carbon dots, graphene, carbon nanotubes, and other nanocarbon materials electrodes is summarized, while the capacitance and energy density of the above nanocarbon electrodes still need to be improved. Then, the preparation and performance of nanocarbon-based composite electrodes comprising transition metal oxides, conductive polymer, and metal–organic framework derived porous carbon are reviewed. Finally, we outline major challenges and propose some ideas on building better nanocarbon-based SC electrodes. Graphic Abstract