Flexible and conductive nanocomposite electrode based on graphene sheets and cotton cloth for supercapacitor

There is currently a strong demand for energy storage devices which are cheap, light weight, flexible, and possess high power and energy densities to meet the various requirements of modern gadgets. Herein, we prepare a flexible and easily processed electrode via a simple "brush-coating and drying" process using everyday cotton cloth as the platform and a stable graphene oxide (GO) suspension as the ink. After such a simple manufacturing operation followed by annealing at 300 degrees C in argon atmosphere, the as-obtained graphene sheets (GNSs)-cotton cloth (CC) composite fabric exhibits good electrical conductivity, outstanding flexibility, and strong adhesion between GNSs and cotton fibers. Using this GNSs-CC composite fabric as the electrode material and pure CC as the separator, a home-made supercapacitor was fabricated. The supercapacitor shows the specific capacitance of 81.7 F g(-1) (two-electrode system) in aqueous electrolyte, which is one of the highest values for GNSs-based supercapacitors. Moreover, the supercapacitor also exhibits satisfactory capacitance in ionic-liquid/organic electrolyte. An all-fabric supercapacitor was also fabricated using pure CC as separator and GNSs-CC composite fabric as electrode and current collector. Such a conductive GNSs-CC composite fabric may provide new design opportunities for wearable electronics and energy storage applications.