1993年のIijimaらによる単層カーボンナノチュrnーブ(SWNT)の発見により,その量産技術や応用にrn関する研究が活発化している.SWNTの合成技術に関rnしてはこれまでに数多くの手法が提案されてきているrnが,量産に向いたものとして,化学気相成長(CVD)法rnが注目されている.%The catalytic reaction mechanism in the growth process of single-walled carbon nanotubes (SWNTs) is considered for carbon monoxide catalytic CVD (COCCVD) and alcohol catalytic CVD (ACCVD) methods. Combinatory CVD experiments were carried out employing a wide variety of catalyst metals, ranging from commonly used transition metals such as Co and Mo to noble metals such as Au and Pt. As a result, we propose that difference in eletronegativity is a key factor to choose a pair of binary catalysts. In the efficient catalyst reaction for a combination of catalyst metals with large electronegativity difference, the metal atom with larger electronegativity functions as a carbon bonding site, and other metal atoms help the dissociation of H_2. For the combination of similar electronegativities, the metals have no work-share. Furthermore, catalytic activity of Au and Pt are demonstrated for COCCVD in addition to the previously reported ACCVD with adequate heat-treatment condition.
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