Ultrafine MnO2 nanowires grown on RGO-coated carbon cloth as a binder-free and flexible supercapacitor electrode with high performance

Abstract

Reduced graphene oxide coated carbon cloth has been used as a substrate for the growth of ultrafine MnO₂ nanowires (CC/RGO/MnO₂), forming binder-free and flexible supercapacitor electrode materials. The experimental results indicate that a maximum area-specific capacitance of 506.8 mF cm⁻² was gained from the CC/RGO/MnO₂ electrode at the current density of 0.128 mA cm⁻². Furthermore, the electrode exhibits excellent cycling stability (98.6% specific capacitance was still retained after 10 000 galvanostatic charge–discharge (GCD) tests when the current density was 1.28 mA cm⁻²). What's more, the area-specific capacitance of the CC/RGO/MnO₂ electrode was hardly changed, when the electrode was operated under bending mechanical conditions. In addition, the charge storage performance and mechanism of the MnO₂ nanostructures was discussed.