Recent advances of carbon dots based emerging materials for supercapacitors applications

Supercapacitors have been regarded as promising and reliable energy storage devices attributed to their high power density, outstanding rate capability and ultralong lifespan, etc. Nonetheless, their practical applicability is still hampered by the unsatisfactory energy density and significant efforts have been undertaken to boost the energy density. As a new and revolutionary derivative member of the carbon family, carbon dots (CDs) stand out in the aspects of electrical conductivity, smaller size, abundant and tunable surface groups, facile fabrication, thus endowing them with great potential in supercapacitors. This review presents the properties of CDs favoring capacitive behavior, and then summarize the advances of CDs's applications in supercapacitors as an electrode material and modifier (including hybrid with carbon, conducting polymers, metal compounds, etc.). The corresponding theoretical calculations are outlined. Finally, the current challenges and prospects for CDs in supercapacitors are proposed to provide perspectives for further development of CDs-based supercapacitors.