Delamination of multilayer graphene nanoribbons on flat substrates

Abstract

Using molecular dynamics simulation, we have shown that multilayer graphene nanoribbons located on the flat surface of the h-BN crystal (on the flat substrate) delaminate due to thermal activation into a parquet of single-layer nanoribbons on the substrate. The delamination of graphene nanoribbons requires overcoming the energy barrier associated with the initial shift of its upper layer. After overcoming the barrier, the delamination proceeds spontaneously with the release of energy. The value of this barrier has been estimated and the delamination of two-layer nanofilms has been simulated. The existence of two delamination scenarios has been shown. The first scenario is the longitudinal (along the long side of the nanoribbon) sliding of the upper layer. The second one is in the sliding of the upper layer with the rotation of the layers relative to each other. The first scenario is common for elongated nanoribbons, the second --- for two-layer graphene flakes having close to a square shape. Keywords: graphene, multilayer nanoribbons, flat substrate, nanoribbon delamination.