Suppression of Metallic Conductivity of Single-Walled Carbon Nanotubes by Cycloaddition Reactions

The high carrier mobility of films of semiconducting single- walled carbon nanotubes ( SWNTs) is attractive for electronics applications, but the presence of metallic SWNTs leads to high off- currents in transistor applications. The method presented here, cycloaddition of fluorinated olefins, represents an effective approach toward converting the "as grown" commercial SWNT mats into high- mobility semiconducting tubes with high yield and without further need for carbon nanotube separation. Thin- film transistors, fabricated from percolating arrays of functionalized carbon nanotubes, exhibit mobilities > 100 square centimeters per volt- second and on- off ratios of 100,000. This method should allow for the use of semiconducting carbon nanotubes in commercial electronic devices and provide a low- cost route to the fabrication of electronic inks.