Lithium storage in polymerized carbon nitride nanobells

Polymerized carbon nitride nanobells (CNNBs) have been intercalated by a la rge amount of Li ions using an electrochemical method. Li nanocrystals are observed on the inside surface of CNNB walls, which is direct evidence that a Li nanocrystal can exist at the micropore structure at a heavy intercala ting level. Graphene layers are expanded and become partly disordered by Li intercalation, while after deintercalation, they are reordered to a certai n degree, and Li nanocrystals disappear. The samples show a reversible Li s torage capacity of 480 mAhg(-1), much higher than 330 mAhg(-1) of commercia l carbon materials used for Li ion batteries. (C) 2001 American Institute o f Physics.