Controlled Oxidative Cutting of Single-Walled\nCarbon Nanotubes

Abstract

The oxidation reaction of piranha solutions with purified HiPco carbon nanotubes was measured\nas a function of temperature. At high temperatures, piranha is capable of attacking existing damage sites,\ngenerating vacancies in the graphene sidewall, and consuming the oxidized vacancies to yield short, cut\nnanotubes. Increased reaction time results in increasingly shorter nanotubes. However, significant sidewall\ndamage occurs as well as selective etching of the smaller diameter nanotubes. On the other hand, room-temperature piranha treatments show the capability of cutting existing damage sites with minimal carbon\nloss, slow etch rates, and little sidewall damage. Combined with a method of introducing controlled amounts\nof damage sites, these room-temperature piranha solutions have the potential to yield an efficient means\nof creating short, cut nanotubes.