Tuning the band gap of graphene nanoribbons (GNR) by chemical edge functionalisation is a promising approach towards future electronic devices based on graphene. The band gap is closely related to the aromaticity distribution and therefore tailoring the aromaticity patterns is a rational way for controlling the band gap. In our work, it is shown how to control the aromaticity distribution and the band-gap in both armchair and zigzag GNRs. We perform periodic density functional theory (DFT) calculations on the electronic structure and the aromaticity distribution, using delocalisation and geometry analysis methods like the six-centre index (SCI) and the mean bond length (MBL). These results are compared with nonequilibrium Green’s function (NEGF) transport property calculations. We also provide a complete description of the relation between band gap, transport properties, and aromaticity distribution along these materials, based on DFT results and Clar’s sextet theory.
Journal: TechConnect Briefs
Volume: 1, Nanotechnology 2014: Graphene, CNTs, Particles, Films & Composites
Published: June 15, 2014
Pages: 29 - 32
Industry sector: Advanced Materials & Manufacturing
Topicss: Carbon Nano Structures & Devices, Graphene & 2D-Materials