respectively. The S-doped CNFs presented high reversible capacities of 460 mA h g -1 at 0.05 A g -1 , and preserved a capacity of 310 mA h g -1 at 1 A g -1 after 1100 cycles, which are ascribed to the large surface area, and considerable defects, and the stable structure associated with the cross-linked network of CNFs. The different heteroatoms doped with CNFs synthesized via aerogel template route is indicated in Table .