• electrochemistry;
  • energy storage;
  • graphene;
  • nanotubes;
  • supercapacitor


A MnO2–CNT–graphene oxide (MCGO) nanocomposite is fabricated using graphene oxide (GO) as a surfactant to directly disperse pristine carbon nanotubes (CNTs) for the subsequent deposition of MnO2 nanorods. The resulting MCGO nanocomposite is used as a supercapacitor electrode that shows ideal capacitive behavior (i.e., rectangular-shaped cyclic voltammograms), large specific capacitance (4.7 times higher than that of free MnO2) even at high mass loading (3.0 mg cm−2), high energy density (30.4–14.2 Wh kg−1), large power density (2.6–50.5 kW kg−1), and still retains approximately 94 % of the initial specific capacitance after 1000 cycles. The advanced capacity, rate capability, and cycling stability may be attributed to the unique architecture, excellent ion wettability of GO with enriched oxygen-containing functional groups, high conductivity of CNTs, and their synergistic effects when combined with the other components. The results suggest that the MnO2–CNT–GO hybrid nanocomposite architecture is very promising for next generation high-performance energy storage devices.