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arXiv · 2009.13936

Band Depopulation of Graphene Nanoribbons Induced by Chemical Gating with Amino Groups

Jingcheng Li·Pedro Brandimarte·Manuel Vilas-Varela·Nestor Merino-Díez·César Moreno·Aitor Mugarza·Jaime Sáez Mollejo·Daniel Sánchez Portal·Dimas G. de Oteyza·Martina Corso·Aran Garcia-Lekue·Diego Peña·Jose Ignacio Pascual
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Abstract

The electronic properties of graphene nanoribbons (GNRs) can be precisely tuned by chemical doping. Here we demonstrate that amino (NH$_2$) functional groups attached at the edges of chiral GNRs (chGNRs) can efficiently gate the chGNRs and lead to the valence band (VB) depopulation on a metallic surface. The NH$_2$-doped chGNRs are grown by on-surface synthesis on Au(111) using functionalized bianthracene precursors. Scanning tunneling spectroscopy resolves that the NH$_2$ groups significantly up-shift the bands of chGNRs, causing the Fermi level crossing of the VB onset of chGNRs. Through density functional theory simulations we confirm that the hole-doping behavior is due to an upward shift of the bands induced by the edge NH$_2$ groups.

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Jingcheng Li, Pedro Brandimarte, Manuel Vilas-Varela, Nestor Merino-Díez, César Moreno, Aitor Mugarza, Jaime Sáez Mollejo, Daniel Sánchez Portal, Dimas G. de Oteyza, Martina Corso, Aran Garcia-Lekue, Diego Peña, Jose Ignacio Pascual. 2020-09-29. Band Depopulation of Graphene Nanoribbons Induced by Chemical Gating with Amino Groups. https://doi.org/10.1021/acsnano.9b08162

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