Unscrolling of multi-walled carbon nanotubes: towards micrometre-scale graphene oxide sheets

Chemical routes toward obtaining graphene materials are commonly used in the field, and one such preparation method is the unzipping of carbon nanotubes into long, thin graphene nanoribbons. In this work, we show that oxidative permanganate treatment of Scroll type multi-walled carbon nanotubes can lead to large, stacked sheets instead of nanoribbons. This difference is suggested to arise from the type of nanotube used, such as the Russian Doll form or Scroll form causing a change in the initial oxidation site location and ultimately leading to an alternate nanotube opening process.