Electronic properties of a semiconducting armchair graphene nanoribbon on SiO_2 are examined using first-principles calculations and taking into account the van der Waals interaction. Unlike semiconducting carbon nanotubes, which exhibit variations in band gap on SiO_2, the nanoribbon is
found to retain its band gap on SiO_2, regardless of the separation distance or the dielectric’s surface type—crystalline or amorphous. The interfacial interaction leads to electron-transfer from the nanoribbon to the dielectric. Moreover, for crystalline SiO_2, the quantity of electron-transfer and the binding energy depend strongly on the type of surface termination and weakly on the binding
sites
