Giant miscanthus (GM) is an Asian grass that can produce biomass in high yields per land area. It can be used as a cathode material in lithium sulfur (Li/S) batteries. Giant-miscanthus-derived activated carbon (GMAC) is prepared via carbonization of GM followed by KOH activation. It is prepared with a large amount of KOH, and thus contained more defects but had a highly porous structure and graphitic cluster lattice. GMAC has a large specific surface area of 3327 m2/g and a large total pore volume of 1.86 cm3/g. The pore volume served as a storage space for the retention of polysulfides, thereby inhibiting the shuttle effect. When a GMAC–sulfur composite cathode is tested in a Li/S battery, an initial discharge capacity of 1148 mAh/g can be attained at 0.1 C. In a cyclic charge–discharge experiment at 1 C, discharge capacities of 529 mAh/g and 248 mAh/g are observed in the first and 200th cycles, respectively.

    Abstract
    1 Introduction
    2 Experimental
        2.1 Synthesis of giant-miscanthus-derived activated carbons
        2.2 Preparation of activated carbon–sulfur composites
        2.3 Electrochemical measurements
        2.4 Characterization of the materials
    3 Results and discussion
    4 Conclusion
    Acknowledgements 
    References

• Geon Hae Lim(Energy Storage Materials Center, Korea Institute of Ceramic Engineering and Technology)
• Ji Su Chae(Energy Storage Materials Center, Korea Institute of Ceramic Engineering and Technology)
• Young‑Lok Cha(Bioenergy Crop Research Center, NICS, RDA, 293‑5 Cheongcheon)
• Yun Chan Kang(Department of Materials Science and Engineering, Korea University)
• Kwang Chul Roh(Energy Storage Materials Center, Korea Institute of Ceramic Engineering and Technology)