Double atomic layers of graphene/monolayer h-BN on Ni(111) studied by scanning tunneling microscopy and scanning tunneling spectroscopy

Using STM, we have directly confirmed the incommensurate stacking of double atomic layers of graphene and monolayer h-BN on Ni(111). The formation of a graphene layer weakens the interfacial interaction between monolayer h-BN and Ni(111), resulting in insulating h-BN layers, while a pristine monolayer h-BN on Ni(111) is metallic. The STS spectra of the double atomic layers showed a tunneling character with a band gap of 0.5 eV.