Fixing graphene-Mn3O4 nanosheets on carbon cloth by a poles repel-assisted method to prepare flexible binder-free electrodes for supercapacitors

Abstract

In this work, Mn3O4 nanosheets were prepared by partially reducing MnO2, and then wrapped by graphene to form the composites. Flexible binder-free electrodes based on graphene-Mn3O4 nanosheets and carbon cloth were prepared with the assistance of poles repel. As electrodes for supercapacitors, the flexible electrodes exhibited a specific capacitance of 502Fg−1 in 1M Na2SO4 at a current density of 1Ag−1. When performed at 5Ag−1, 84% of the original specific capacitance (300Fg−1) can be retained after 1000 cycles. Simultaneously, the comparison experiment between the binder-free and binder-contained electrodes confirmed the larger specific capacitance, lower impedance, and better rate capability of the former one. The strategy developed in this work may open up a general approach of poor conductivity of metal oxide-based binder-free electrodes for high-performance energy-storage devices.