Mass specific performance of halogen and alkali metal based dopants in carbon nanotube wiring

Abstract

High electrical conductivity, low mass density, and compatibility with spin fabrication processes have made carbon nanotube (CNT) based conductors a prime candidate for the replacement of copper in power transmission applications. Experimental research has successfully employed chemical doping to produce CNT wiring with very high electrical conductivity. However, due to the high molecular weight of the most successful dopants, these CNT based conductors show a mass specific conductivity very similar to that of copper and are therefore of limited interest in mass constrained applications, such as aircraft design. Ab initio analysis of the mass specific performance of nine widely studied dopants, including halogens, interhalogens, alkali metals, and alkali metal halides, suggests the principal reasons for their lack of success in producing high mass specific conductivity CNT based wiring. Their disparate doping effects on metallic CNTs, semiconducting CNTs, metallic nanotube junctions, and semiconducting nanotube junctions form a near orthogonal set, so that in the mix of metallic and semiconducting nanotubes typical of experimental investigations, much of the conductor mass is parasitic, no matter which of the dopants is applied.