[8p-Z29-1~8] 17.1 Carbon nanotubes & other nanocarbon materials

▲ [8p-Z29-1] Etching effect of carbon dioxide on carbon nanotube growth at high temperature

〇(D)Mengyue Wang¹, Keisuke Nakamura¹, Michiharu Arifuku², Noriko Kiyoyanagi², Masaaki Ikeda², Yoshihiro Kobayashi¹ (1.Osaka Univ., 2.Nippon Kayaku)

Keywords:carbon nanotube, high temperature growth, etchant

Formed simultaneously with CNTs, amorphous carbon (a-C) adsorbs on the surface of catalysts or growth seeds and blocks the active sites. To remove such by-product, relied on oxidation reaction, kinds of etchants have been employed in the growth procedure. As part of the commoner used etchants, H₂O and CO₂ have been proved to perform some desired etching effects. In the reports we have presented before, when the growth temperature raised up to 1000℃, part of a-C might not be removed, especially when using ethylene as the carbon source. This result reminded us the importance of etchant participated in growth system. In this project, we tried to figure out the etching ability of CO₂ in two-stage growth and made a comparison with H₂O. It has been found that, different with the etching capacity of H₂O performed at 1000℃, CO₂ prefers gentler etching effect with fewer CNTs damages even there got excess injection amount, which presented that the CO₂ could be a more efficient and stable etchant in CNTs’ growth at high temperature.