Determining synthesis region of the single wall carbon nanotubes in arc plasma volume

Abstract

Arc discharge is one of the most efficient and environmental friendly method to synthesize Single Wall Carbon Nanotube (SWCNT). However, due to the ultra-fast synthesis procedure, localization of the SWCNT synthesis in an arc discharge plasma volume in situ has been a long standing problem. This relates to the ability of controlling volumetric synthesis of nanostructures in plasmas in general. In order to better understand the mechanism of the nanotube growth in plasma, we have developed an actuator driven high-speed system that is able to extract material from the arc plasma volume during the synthesis procedure. The majority of the SWCNTs produced using arc discharge method are semiconducting with diameter of about 1.5nm. It is shown that the growth region of SWCNTs is between 3mm to 11mm away from the center of the arc

Can We Optimize Arc Discharge and Laser Ablation for Well-Controlled Carbon Nanotube Synthesis?

“…The procedure is economical since it does not demand high pressure and expensive inert gases. Rotating plasma technique is interesting useful to increase the yield [121]. It involves the uniform distribution of discharges which help to stabilize plasma in large volume.…”

“…Based on these results, one can suggest an active electromagnetic device that might be introduced for the control of the catalyst nanoparticles’ nucleation and the SWCNT and graphene growth. Another strategy has recently been published by Fang et al [121] who synthesized semiconducting SWCNT with diameter of about 1.5 nm by using an actuator-driven high-speed system that is able to extract material from the arc plasma volume during the synthesis procedure.

Fig. 9Photo of the applied magnetic field at arc plasma ( a ), computed carbon and catalyst particle density distribution showing the regions with preferable conditions for chiral CNT synthesis ( b ), scanning electron microscope image of graphene sheets ( c ), and TEM image of SWCNT bundles with specific chirality ( d ).

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Synthesis of nanoparticles in carbon arc: measurements and modeling

“…Some nanomaterials can only be synthesized with plasma and for some, plasma approach is favored due to industrial scale yield, better selectivity and improved material characteristics [9]. Carbon arc is a widely used plasma source for making a variety of carbon nanomaterials of various structures such as fullerenes, carbon nanotubes, nano-horns, nanofibers, graphene, etc [10][11][12][13][14][15][16][17][18][19]. Particularly in the arc the single-walled nanotubes, nanoparticles and nano-horns are synthesized, in flight, in the gas phase, as opposed to the surface growth in chemical vapor deposition 1 Currently in Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.…”

Complex structure of the carbon arc discharge for synthesis of nanotubes

“…Ablation of graphite electrodes by an arc discharge [1,2] and laser vaporization of graphite targets [3,4] are well established methods for a potentially large-scale production of these nanostructures.The DC arc discharge method has the advantages of being less expensive and easier to implement than laser vaporization techniques. For synthesis of carbon nanotubes (CNTs), a DC arc discharge with a consumed graphite anode at atmospheric pressure helium gas is commonly used [5][6][7]. Typical parameters of this carbon arc are: arc current of 50-100 A, arc voltage of 10-20 V, and helium gas pressure of 500-600 Torr.…”