A first principles study of a piece of carbon nanoribbon on nickel along the zigzag edge

The adsorption of a piece of graphene nanoribbon on Ni surfaces, edges, and steps along the zigzag edge are studied with first principle calculations. The absolute value of the adsorption energy per contacting point on the (100) surface is higher than that on the (111) surface. The edge effects on the graphene adsorption on one side of various edges can be ignored because the cohesive energies and the bond lengths do not change too much on edges compared with that on the bare surfaces. The vertical edge adsorption is not as strong as the one side edge adsorption. For the step adsorption, extra Ni-C bonds form at the interface, the absolute values of the adsorption energies on steps increase and the C-C bond lengths near interfaces are longer than that on the surfaces and edges. For carbon nanotube (CNT) or graphene growth on Ni nanoparticles, steps are at the outside portions of the particles between different facets. Since stronger adsorption and longer C-C bond length near the interface, especially on the steps, may benefit the CNT growth, it can help us understand the relationship between the diameter of CNTs and the size of the Ni particles. (C) 2012 Elsevier B.V. All rights reserved.