Core-shell carbon-coated CuO nanocomposites: A highly stable electrode material for supercapacitors and lithium-ion batteries

Abstract

Herein we present a simple method for fabricating core-shell mesostructured CuO@C nanocomposites by utilizing humic acid (HA) as a biomass carbon source. The electrochemical performances of CuO@C nanocomposites were evaluated as an electrode material for supercapacitors and lithium-ion batteries. CuO@C exhibits an excellent capacitance of 207.2 Fg-1 at a current density of 1 Ag-1 within a potential window of 0-0.46 V in 6 m KOH solution. Significantly, CuO electrode materials achieve remarkable capacitance retentions of approximately 205.8 Fg-1 after 1000 cycles of charge/discharge testing. The CuO@C was further applied as an anode material for lithium-ion batteries, and a high initial capacity of 1143.7 mAhg-1 was achieved at a current density of 0.1 C. This work provides a facile and general approach to synthesize carbon-based materials for application in large-scale energy-storage systems.