Hybrid carbon nanotube-graphene monolayer films: Regularities of structure, electronic and optical properties

Using original technique we have constructed the topological models of hybrid carbon nanotube (CNT)-graphene film on the basis of two graphene monolayers with zigzag tubes between them. The mechanism of energy favorable covalent bonding between the tubes and graphene sheet was established for the first time. We found that only tubes (n, 0) with only even number n can form thermodynamically stable covalently bonded structures with graphene sheets. It was shown that the most thermodynamically stable topological models were composites with the tubes (10,0), (12,0), (14,0), (16,0) and (18,0) at the intertube distance of 9, 10, 11, 12 and 13 hexagons (the enthalpy of formation < −0.2 kcal/mol atom). We found that these topological models except composites with the tubes (10, 0) demonstrate the semimetal type conductivity at the step of 10 hexagons and more. It was also shown that composites can serve the basis for optical antennas because they can absorb electromagnetic waves in the optical range and in the UV region. Using tubes of different diameter and changing the step of their period it is possible to achieve absorption of wide range waves.

The fragment of 2D-composite atomistic model using by SCC DFTB2 method.677