ABSTRACT
A carbon nanotube can be viewed as a graphene sheet rolled up
into a seamless cylinder. This implies, conversely, that longitudinal
cutting (i.e., unzipping) of nanotubes leads to a set of one-atom-thick
graphene sheets having very narrowwidths and straight edges. Such
a thin strip of carbon sheet, termed a graphene nanoribbon, was
theoretically predicted to conduct electrons well,a being transparent
and mechanically strong. Hence, it has been touted as a promising
material for use in electronic devices such as field-effect transistors,
which form the basis of solar cells, displays, and microchips in
computers. To understand and fully make use of its interesting
properties, methods for large-scale production are indispensible.
Until recently, however, graphene nanoribbons have proved harder
to produce than nanotubes; early techniques based on lithographic
patterning [398-402], sonochemical methods [403, 404], chemical
vapor deposition (CVD) [405, 406], and nanocutting [407-409]
could not make nanoribbons in large amounts or with controlled
widths.
