Though for decades silicon has been the standard material for transistors, there is much hype over the possibility of replacing it with new nanomaterials, such as flexible, one-atom-thick sheets of carbon known as graphene. However, for graphene to have the necessary semiconducting properties, it must be cut into ribbons less than 10 nanometers wide.
Material scientists are making graphene ribbons by unfurling carbon nanotubes. One group stuck the nanotubes onto a polymer film and used ionized argon gas to slice open each tube, resulting in ribbons as narrow as 6 nanometers wide. Another group exposed nanotubes to sulfuric acid and potassium permanganate, a strong oxidizing agent, which strained the carbon bonds and caused the tubes to unzip lengthwise, as shown here.
Some researchers are investigating other promising ways to make graphene an effective semiconductor, like using two-layer graphene along with a special insulating polymer or punching holes in graphene to create a semiconducting "nanomesh," but it remains to be seen if any of these techniques will produce viable chips.
Image: Dmitry V. Kosynkin, Rice University