Study of the Effect of Anode/Cathode Geometry on the Yield Rate and Quality of the MWCNTs Synthesized by Submerged Arc Discharging

The main objective of the present paper is to clarify the effect of anode/cathode geometry combinations on the yield rate and quality of the Multiwalled Carbon Nanotubes (MWCNTs) produced by submerged arc discharge technique. The effects of current intensity and the discharging medium (solvent) are also investigated. The morphology and crystalline perfection of the produced MWCNTs are confirmed by transmission electron microscopy (TEM) and Electron diffraction. Thermogravimetric analysis (TGA) is conducted to check the quality of the MWCNTs in a quantitative manner. The flat ended anode/cathode combination of diameters 4 and 12 mm respectively exhibited the highest yield at 70 A using deionized water as solvent. Through careful selection of the process parameters, the yield rate of MWCNTs obtained is found to be higher than most of the reported values in literature. However, the best quality of MWCNTs with purity as high as 95%, average thermal stability of 745°C as well as good batch homogeneity, is obtained with KCl solution and tapered male/female anode combination. The best quality MWCNTs is used successfully as reinforcement for A356 aluminum silicon composite.