Thermodynamics of formation of carbon nanotubes catalyzed by nickel

Thermodynamic size conditions for transitions from a Ni thin film to a Ni particle and then from the Ni particle wrapped with carbon shell to a Ni nanoline are analyzed. It is found that the radius of a transformed particle must be 1.5 times larger than the thickness of the film, and the radius of the formed nanoline have to be larger than half of the radius of the particle. During the above transitions, the wrapped carbon shell on the particle is transformed to a carbon nanotube, which is catalyzed by the shape change of the Ni particle through their semicoherent interface. Since the transition temperature reaches 62% of melting temperature of the Ni thin film, the transitions can proceed kinetically. The above predictions are supported by experimental results. q1999 Elsevier Science B.V. All rights reserved.