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arXiv · 1705.07045

Doping of Graphene Nanoribbons via Functional Group Edge Modification

Eduard Carbonell-Sanromà·Jeremy Hieulle·Manuel Vilas-Varela·Pedro Brandimarte·Mikel Iraola·Ana Barragán·Jingcheng Li·Mikel Abadia·Martina Corso·Daniel Sánchez-Portal·Diego Peña·Jose Ignacio Pascual
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Abstract

We report on the on-surface synthesis of 7 armchair graphene nanoribbons (7-AGNRs) substituted with nitrile (CN) functional groups. The CN groups are attached to the GNR backbone by modifying the 7-AGNR precursor. While many of these groups survive the on-surface synthesis, the reaction process causes the cleavage of some CN from the ribbon backbone and the on-surface cycloisomerization of few nitriles onto pyridine rings. Scanning Tunneling Spectroscopy and Density Functional Theory reveal that CN groups behave as very efficient n-dopants, significantly downshifting the bands of the ribbon, and introducing deep impurity levels associated to the nitrogen electron lone pairs.

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Eduard Carbonell-Sanromà, Jeremy Hieulle, Manuel Vilas-Varela, Pedro Brandimarte, Mikel Iraola, Ana Barragán, Jingcheng Li, Mikel Abadia, Martina Corso, Daniel Sánchez-Portal, Diego Peña, Jose Ignacio Pascual. 2017-05-19. Doping of Graphene Nanoribbons via Functional Group Edge Modification. https://arxiv.org/abs/1705.07045

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