Thermal and electrical conduction properties of vertically aligned carbon nanotubes produced by water-assisted chemical vapor deposition

We present both thermal and electrical conduction properties of vertically aligned carbon nanotubes (VACNTs), synthesized by the water-assisted chemical vapor deposition method using Fe-Ti-O nanoparticles as catalyst Thermal diffusivity and electrical resistance of VACNTs have been measured by the laser flash method and direct current four-terminal method, respectively The VACNTs are found to have thermal diffusivities of the same order as isotropic graphite and the electrical characteristics of semiconductors The electrical resistance shows a T(-1/4) temperature dependence, which implies that the conduction of electrons is dominated by 3D Mott variable range hopping (C) 2010 Elsevier Ltd All rights reserved