Cathodic Arc Discharge for Synthesis of Carbon Nanoparticles

2011-11-01
In this chapter, the authors report further experimental details and several physical analyses of the floating powder and propose a model for the formation mechanism. They discussed the ability to analyze carbon nanoparticle formation in terms of a charged dusty plasma process. The detected carbon nanoparticles using a Langmuir probe technique are in agreement with the presence of fullerene-sized molecules in the plasma. The plasma can also be visually observed to surround the anode, indicating the direction of plasma expansion. There is a plasma zone between electrodes surrounded by a gas bubble due to vaporization of the surrounding liquid, as the arc temperature is estimated to be around 4000 K. The extremely sharp temperature gradient in the gas bubbles emanating from the hot plasma region to the gas–water interface is essential to cause rapid solidification of the vaporized carbon. Subsequent to the formation of onions, carbon particles coagulate into larger van der Waals crystals.

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Citation Formats
H. E. Ünalan, Cathodic Arc Discharge for Synthesis of Carbon Nanoparticles. 2011, p. 163.