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arXiv · 1910.01385

Band Gap of Atomically Precise Graphene Nanoribbons as a Function of Ribbon Length and Termination

Leopold Talirz·Hajo Söde·Shigeki Kawai·Pascal Ruffieux·Ernst Meyer·Xinliang Feng·Klaus Müllen·Roman Fasel·Carlo A. Pignedoli·Daniele Passerone
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Abstract

We study the band gap of finite $N_A=7$ armchair graphene nanoribbons (7-AGNRs) on Au(111) through scanning tunneling microscopy/spectroscopy combined with density functional theory calculations. The band gap of 7-AGNRs with lengths of 6 nm and more is converged to within 0.1 eV of its bulk value of 2.3 eV, while the band gap opens by several hundred meV in very short 7-AGNRs. The termination has a significant effect on the band gap, doubly hydrogenated termini yielding a lower band gap than singly hydrogenated ones.

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Leopold Talirz, Hajo Söde, Shigeki Kawai, Pascal Ruffieux, Ernst Meyer, Xinliang Feng, Klaus Müllen, Roman Fasel, Carlo A. Pignedoli, Daniele Passerone. 2019-10-03. Band Gap of Atomically Precise Graphene Nanoribbons as a Function of Ribbon Length and Termination. https://doi.org/10.1002/cphc.201900313

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