The electrochemical capacitive properties of biomass-derived activated carbons are closely dependent on their microscopic structures. Here, activated carbon fibers (ACFs) were prepared from natural cattail fibers by carbonization and further chemical activation. The activation temperature affected on the microscopic structures and electrochemical properties of the activated carbon fibers. The results show that the optimum activation temperature is 800 °C. And the as-prepared ACF- 800 possesses high micropore specific surface area of 710.4 m2 g− 1 and micropore volume of 0.313 cm3 g− 1, respectively. For supercapacitor applications, the ACF-800 displays a high specific capacitance of 249 F g− 1 at a current density of 0.05 A g− 1, excellent rate performance and cycle stability in a three-electrode system. The excellent electrochemical performance indicated that the obtained activated carbon fibers could be a promising electrode material in supercapacitor.

    Abstract
    1 Introduction
    2 Experimental
        2.1 Preparation of ACFs
        2.2 Characterization
        2.3 Electrochemical measurements
    3 Results and discussion
    4 Conclusions
    Acknowledgements 
    References

• Lizhong Bai(Department of Materials Science and Engineering, Shanxi Institute of Technology)
• Feng Zhao(Department of Materials Science and Engineering, Shanxi Institute of Technology)
• Lijun Bai(Department of Materials Science and Engineering, Shanxi Institute of Technology)
• Chaonan Wang(Department of Materials Science and Engineering, Shanxi Institute of Technology)