Field-induced self-assembly formation of carbon nanotube filaments triggered via gas discharge breakdown

Abstract

Self-assembly formation of dense carbon nanotube (CNT) filaments is demonstrated with gas discharge breakdown. CNT filament formation is triggered by irradiation of ions generated by gas discharge breakdown on a CNT mat placed on a cathode. The ion irradiation causes detachment of CNTs from the CNT mat on the cathode. Those CNTs are collected on a counter electrode and reassembled into filaments from the effect of an electric field. We examined the CNT filament formation characteristics using the combination of a plate-shaped cathode covered with a CNT mat and a wire-shaped anode as the discharge electrodes. CNT filament formation strongly depended on the discharge gas (Ar) pressure. Low Ar gas pressure of 4–6 kPa resulted in dense tree-like CNT filament formation on the anode. Addition of a collection electrode to the anode and cathode resulted in drastic enhancement of CNT filament formation. Dense and long filaments, approximately 10 mm in length, formed on the collection electrode. These results indicate that CNT filament formation by discharge breakdown can be used as a versatile dry spinning method for various kinds of CNTs that are unspinnable by conventional methods.