Doped graphene nanoribbons hold promise for next gen electronics

By seamlessly stringing together doped and undoped graphene pieces, the team was able to form heterojunctions in the nanoribbons, thereby fulfilling a basic requirement for electronic current to flow in only one direction when voltage is applied. Furthermore, the team has successfully managed to remove graphene nanoribbons from the gold substrate on which they were grown and to transfer them onto a non-conductive material. Instead of always using the same 'pure' carbon molecules, the researchers used additionally doped molecules – molecules provided with 'foreign atoms' in precisely defined positions, in this case nitrogen. By stringing together 'normal' segments with nitrogen doped segments on a gold surface, they found that so called heterojunctions could be created between the individual segments. The researchers have shown that these display similar properties to those of a classic p-n-junction. Because of the sharp transition at the heterojunction interface, the new structure allows electron/hole pairs to be efficiently separated when an external voltage is applied. While the breakthrough is certainly promising, the researchers estimate that it may still take about 10 to 15 years before the first electronic switch made of graphene nanoribbons can be used in a product.