A hetero-epitaxial-double-atomic-layer system of monolayer graphene/monolayer h-BN on Ni(111)

A double-atomic-layer system of monolayer graphene/monolayer h-BN has been prepared in an epitaxial manner on Ni(111) surface. The graphene overlayer formation changes drastically the pristine interface between the h-BN layer and Ni(lll). As a result, a peculiar property of the pristine monolayer h-BN on Ni(111) changes to a bulk-like one. The pi-d orbital hybridization at the interface disappears. Accordingly, a metallic character of monolayer h-BN disappears and softening TO phonons return to the normal one. The reduced lattice constant of h-BN presumably returns to the bulk one. The same phenomenon occurs by surface contaminations instead of monolayer graphene formation. (C) 2000 Published by Elsevier Science Ltd.