Novel Nanostructures Based On Graphene Ribbons: Molecular Dynamics Simulation

Graphene, a flat monolayer of carbon atoms tightly packed into a two-dimensional honeycomb lattice, is a rapidly rising star on the horizon of materials science and condensed-matter physics. Graphene nanoribbons have also attracted much attention. Using molecular dynamics simulation techniques, we have studied the thermal stability of zigzag graphene ribbons and armchair graphene ribbons. We have also studied the structures and thermal stability of composite nanomaterials combining graphene nanoribbons with semiconductor and metal nanostructures and found a number of novel nanosystems with unique structural properties.Using the Lindemann parameter, we show that the melting temperature of zigzag graphene ribbons and armchair graphene ribbons are about 5000K and 4500K respectively. Zigzag graphene ribbons is more stable. Our results reveal that the melting of graphene ribbons always starts from its edges.We have studied the formation processes of silicon nanoparticles on edges of graphene ribbons. We found that, Si atoms in a gas state can be absorbed on the edges of zigzag graphene ribbons, forming different types of silicon nanostructures under different temperature, namely, amorphous clusters, chain structures, and defective chain structures in the interval of 300K≤T<2000K, 2000K≤T≤2800K, 2800K