Effect of cerium ions in an arc peripheral plasma on the growth of radial single-walled carbon nanotubes
- Graduate School of Environmental Studies, Tohoku University, Sendai 980-8579 (Japan)
Radial single-walled carbon nanotubes (radial SWCNTs) are formed by using a direct current (dc) arc discharge when carbon and metal atoms are mixed in a gas phase after the vaporization and cooled together in a liquid droplet. Since SWCNTs sprout through the precipitation of saturated carbon atoms from liquid droplets during cooling, a mass synthesis of radial SWCNTs can be achieved when a large number of liquid droplets are generated. In order to understand the effects of arc peripheral plasma parameters (electrons, ions, radical atoms, and molecules) on the growth of radial SWCNTs, the optimum production efficiency of radial SWCNTs is investigated by superimposing a radio-frequency (rf) plasma on the thermal arc plasma and controlling the arc peripheral plasma density. Two parameters--the rf power and the dc potential--of the rf electrode, which is equipped above 20 mm from the center of an arc-discharge point, are changed with the constant He pressure (200 Torr), dc arc current (75 A), and power (2000 W). The production yield of radial SWCNTs is found to be enhanced under the condition of the rf power of 100 W and the dc component of the rf electrode voltage of -22 V, revealing that the optimum ion flux and ion bombardment energy are important key parameters for the formation of radial SWCNTs.
- OSTI ID:
- 20719669
- Journal Information:
- Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 9 Vol. 98; ISSN JAPIAU; ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
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