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

• Published in: Carbon (New York) Vol. 49; no. 1; pp. 294 - 298
• Main Authors: Okamoto, Atsuto, Gunjishima, Itaru, Inoue, Takashi, Akoshima, Megumi, Miyagawa, Hidenori, Nakano, Tomohito, Baba, Tetsuya, Tanemura, Masaki, Oomi, Gendo
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2011; Elsevier
• Subjects: Alignment; Carbon; Carbon nanotubes; Catalysis; catalysts; Chemical vapor deposition; Chemistry; Colloidal state and disperse state; Cross-disciplinary physics: materials science; rheology; Electrical conduction; electrical conductivity; Electrical resistance; electrons; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; General and physical chemistry; graphene; lasers; Materials science; nanoparticles; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Physics; Semiconductors; Specific materials; temperature; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; thermal conductivity; Thermal diffusivity; vapors; water; Semiconductor materials; Catalysts; Electrical properties; Carbon nanotubes; Diffusivity; CVD; Nanoparticles; Direct current; Lasers; Graphite; Steam; Electric resistivity; Electrical characteristic; Thermal conduction; Electrons
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2010.09.024

[Display omitted] ► VACNTs are synthesized by catalytic-CVD method using both Fe–Ti–O catalysts and a small amount of H 2O vapor. ► The thermal diffusivity of VACNTs is of the order of that of isotropic graphite. ► The temperature dependences of electrical resistance are characteristics of semiconductors. ► The anisotropy ( R ⊥/ R ∥) gradually increases with decreasing temperature. 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.