Core-Shell Tubular Nanostructured Electrode of Hollow Carbon Nanofiber/Manganese Oxide for Electrochemical Capacitors

Here we propose a core-shell tubular nanostructure consisted of hollow carbon nanofiber and manganese oxide (MnO2) for the application of high capacitance electrochemical capacitors. Hollow nanostructured carbon nanofibers are prepared using an electrospinning technique with a dual nozzle. The hollow channel of carbon nanofibers enables the uptake of MnO2 precursor solution inside the hollow carbon nanofiber, leading to the formation of MnO2 layer on both the inner and outer surfaces of hollow carbon nanofiber. The utilization of both surfaces of hollow carbon nanofiber increases the effective reaction sites of electrode materials contacted with an electrolyte as well as maximizes the loading mass of MnO2 on the surface of hollow carbon nanofiber (94% compared to carbon contents), consequently enabling the fabrication of electrochemical capacitors with the increased specific capacitance of 237 F/g.