Flute type micropores activated carbon from cotton stalk for high performance supercapacitors

Abstract Flute type micropores activated carbon (FTMAC) has been successfully obtained from cotton stalk via KOH-chemical activation method. The synthesized carbon material exhibits an ordered pore structure with high specific surface area of 1964.46 m 2 g −1 and pore volume of 1.03 m 3 g −1 . The assembled FTMAC-based electrode delivers a high specific capacitance of 254 F g −1 at a current density of 0.2 A g −1 in 1 M H 2 SO 4 aqueous electrolyte. It still can maintain 221 F g −1 at a current density of 10 A g −1 , demonstrating a good rate capacity (87% retention), as well as long cyclic stability of 96% capacitance retention after 10000 charging and discharging cycles at current density of 1 A g −1 . Moreover, the symmetric supercapacitor can deliver a high energy density of 18.14 W h kg −1 and a power density of 450.37 W kg −1 which is operated in the voltage range of 0–1.8 V.