Highly conductive electrospun carbon nanofiber/MnO2 coaxial nano-cables for high energy and power density supercapacitors

► Highly conductive carbon nanofibers are used as the support backbone for MnO2 for supercapacitor electrode. ► The correlation of the carbon nanofibers/MnO2 electrode conductivity and the electrochemical performance is investigated. ► The carbon nanofibers/MnO2 coaxial nanostructure shows enhanced specific capacitance up to 1.1 F cm−2 and 311 F g−1.