High sulfur loading in activated bamboo-derived porous carbon as a superior cathode for rechargeable Li–S batteries

Biomass bamboo-derived porous carbon with a surface area up to 1565.4m2g−1 and total pore volume of 0.95cm3g−1 was synthesized via simple activation and pyrolysis routes. This porous carbon matrix can load electroactive sulfur as high as 86wt%, which still delivered very stable cycling performance and great rate capability. [Display omitted] A novel type of porous carbon material for Li–S batteries was obtained by simple pyrolysis of natural bamboo waste at 850°C. The activated bamboo-derived carbon (A_BC) contains abundant micropores and mesopores, possessing a large surface area of 1565.4m2g−1 and total pore volume of 0.95cm3g−1, which are larger than vast majority of biomass materials. All these advantages contribute to improving sulfur loading in the A_BC matrix materials, and a high sulfur content of 86wt% in the A_BC/S composite can be achieved. As the cathode for Li–S batteries, it displayed superior electrochemical properties, with an initial discharge capacity of 1160mAhg−1 at 0.1C (1C=1675mAg−1) and 1050mAhg−1 remained after ten cycles. Further cycled at 0.2C for one hundred cycles, reversible capacity of 930 and 710mAhg−1 was reserved for the first and the 100th cycle, respectively. Further increasing to 0.5C and 1C, it still showed capacities of 695 and 580mAhg−1 with coulombic efficiency over 95%, suggesting this porous A_BC could be a superior carbon matrix for high sulfur loading as the cathode of rechargeable Li–S batteries.