Dominant Formation of the Carbon Nanocoils at Low Temperature
The single helix type carbon nanocoils were formed under the low temperature (550°C) condition. For the formation of the carbon nanocoils, C2H2 was used as a source gas and SF6 was used as an additive gas under the thermal chemical vapor deposition system. The morphologies of as-grown carbon materials at the low temperature (550°C) and the mass ratios of product/catalyst were investigated according to the ratio of C2H2/ SF6 flow and the injection times of SF6 and C2H2 flows. The conversion efficiency from the carbon source gas (C2H2) to the as-grown carbon materials was estimated using the mass ratios of product/catalyst. The sample having the ratio of C2H2/SF6 flow = 50 had the highest conversion efficiency. For the dominant formation of the single helix type CNCs, the optimal ratio of C2H2/SF6 flow was determined to be around 10. As the growth aspect of the single helix type CNCs under the optimal ratio of C2H2/SF6 flow, the formation of the CNCs was understood to be initiated within the reaction time of 5min after the formation of the carbon nanofilaments. The detailed growth mode of the CNCs was proposed.
Prof. Seungho Hong
D. C. Kim and S. H. Kim, "Dominant Formation of the Carbon Nanocoils at Low Temperature", Key Engineering Materials, Vol. 744, pp. 446-452, 2017