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

► The adsorption of zigzag graphene on Ni (1 0 0) is stronger than that on Ni (1 1 1). ► The edge effect of the zigzag graphene on Ni surfaces can be ignored. ► The zigzag graphene adsorption on steps is strong than the edge adsorption. ► Stronger adsorption at the steps benefit the CNT growth. ► Step adsorption may control the CNT diameter for CNT growth on Ni particles.