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

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.

7 pages with 5 figures and 4 page supplementary information. This document is the unedited Author's version of a Submitted Work that was subsequently accepted for publication in ACS Nano, copyright American Chemical Society after peer review

References in corpus (2)

• Graphene Spintronics
• Width-Dependent Band Gap in Armchair Graphene Nanoribbons Reveals Fermi Level Pinning on Au(111)