The tube-like CNFs with cone-shaped structure were synthesized by catalytic pyrolysis of methane. The outer surface of purified CNFs was decorated with Ni-P alloy particles having polycrystalline or nanocrystalline structure instead of amorphous structure. The low Ni-P content appeared to be more efficient to cover the outer surface of CNFs. The electrochemical discharge capacity increased with increasing the Ni-P content on the outer surface of CNFs owing to the synergistic effect between metal and carbon in the electrochemical reaction. The heat treatment contributed to the higher crystallization of surface alloy and improvement of the electrochemical capacity of the composite. (C) 2003 Elsevier Science B.V. All rights reserved.