Highly conductive carbon–CoO hybrid nanostructure arrays with enhanced electrochemical performance for asymmetric supercapacitors

Highly conductive carbon–CoO nanowire array electrodes on 3D nickel foam were designed with ultrahigh specific capacitance (3282.2 F g−1), approaching the CoO theoretical value. Assembled into an asymmetric supercapacitor, the energy density is ∼58.9 W h kg−1, a record among Co-based supercapacitors.