Water-assisted highly enhanced crystallographic etching of graphene by iron catalysts*
Xue Lei-Jianga), Yu Fangb), Zhou Hai-Qingb)†, Sun Lian-Fengb)‡
       
Fabrication of crystallographically oriented nanoribbons with smooth edges and different widths after the addition of water vapor. (a) GNRs with width about 25–58 nm. (b) The widths of GNRs can be as narrow as 10 nm, which can be potentially used as building components in field-effect transistors.