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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 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 homemade supercapacitor was fabricated. The supercapacitor shows the specific capacitance of 81.7 F g À1 (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.

Business costs and energy/environmental concerns have increased interested in biomass materials for production of activated carbons, especially as electrode materials for supercapacitors or as solid-state adsorbents in CO₂ adsorption area. In this paper, waste celtuce leaves were used to prepare porous carbon by air-drying, pyrolysis at 600 °C in argon, followed by KOH activation. The as-prepared porous carbon have a very high specific surface area of 3404 m²/g and a large pore volume of 1.88 cm³/g. As an electroactive material, the porous carbon exhibits good capacitive performance in KOH aqueous electrolyte, with the specific capacitances of 421 and 273 F/g in three and two-electrode systems, respectively. As a solid-state adsorbent, the porous carbon has an excellent CO₂ adsorption capacity at ambient pressures of up to 6.04 and 4.36 mmol/g at 0 and 25 °C, respectively. With simple production process, excellent recyclability and regeneration stability, the porous carbon that was derived from celtuce leaves is among the most promising materials for high-performance supercapacitors and CO₂ capture.

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