Cutting single-walled carbon nanotubes

Abstract

A two-step process is utilized for cutting single-walled carbon nanotubes (SWNTs).The first step requires the breakage of carbon–carbon bonds in the lattice whilethe second step is aimed at etching at these damage sites to create short, cutnanotubes. To achieve monodisperse lengths from any cutting strategy requires controlof both steps. Room-temperature piranha and ammonium persulfate solutionshave shown the ability to exploit the damage sites and etch SWNTs in acontrolled manner. Despite the aggressive nature of these oxidizing solutions, theetch rate for SWNTs is relatively slow and almost no new sidewall damage isintroduced. Carbon–carbon bond breakage can be introduced through fluorination to∼C2F, and subsequent etching using piranha solutions has been shown to be very effective incutting nanotubes. The final average length of the nanotubes is approximately 100 nm withcarbon yields as high as 70–80%.