On‐surface Synthesis of a Chiral Graphene Nanoribbon with Mixed Edge Structure

Abstract

Chiral graphene nanoribbons represent an important class of graphene nanomaterials with varying combinations of armchair and zigzag edges conferring them unique structure-dependent electronic properties. Here, we describe the on-surface synthesis of an unprecedented coveedge chiral GNR with a benzo-fused backbone on a Au(111) surface using 2,6-dibromo-1,5-diphenylnaphthalene as precursor. The initial precursor self-assembly and the formation of the chiral GNRs upon annealing are revealed, along with a relatively small electronic bandgap of approximately 1.6 eV, by scanning tunnelling microscopy and spectroscopy.

Atomically precise graphene nanoribbons: interplay of structural and electronic properties

“…Although chGNRs are predicted to have interesting electronic properties, such as width-dependent band gaps 28 or spin-polarized edge state, 6,135 only two (undoped) chGNRs are so far experimentally available: the (3,1)-chGNR (56) 71 and a benzo-fused (2,1)-chGNR (58). 204 In addition, current precursor design methods cannot easily be adapted to make either wider chGNRs or chGNRs with other edge orientations.…”

Preparation, Supramolecular Organization, and On-Surface Reactivity of Enantiopure Subphthalocyanines: From Bulk to 2D-Polymerization

“…The peripheral halogens that introduce the SubPc chirality can be exploited to polymerize the molecules by means of an Ullman coupling processes. , Many of such on-surface chemical reactions have enabled the synthesis of complex systems otherwise impossible to prepare in conventional solution (or heterogeneous) chemistry . In this context 2D π-extended polymers are interesting due to their potential use in optoelectronic devices, where chirality , or porosity endows intriguing additional properties. To date, the preparation of a 2D π-polymer that combines chirality and porosity into a single framework remains an open challenge.…”

Precision Synthesis of Boron‐Doped Graphene Nanoribbons: Recent Progress and Perspectives

“…[ 13–15 ] On the other hand, the edge configuration of chiral GNRs bearing the armchair and zigzag edges are characterized by a chiral vector (n, m) which connects crystallographically equivalent sites along the edge, and their physiochemical properties, such as electronic band structures and magnetic properties, are highly dependent on the chiral vector. [ 16 ]…”

“…[13][14][15] On the other hand, the edge configuration of chiral GNRs bearing the armchair and zigzag edges are characterized by a chiral vector (n, m) which connects crystallographically equivalent sites along the edge, and their physiochemical properties, such as electronic band structures and magnetic properties, are highly dependent on the chiral vector. [16] Besides the edge structure and width control, the introduction of heteroatoms into GNRs also represents a feasible strategy to tune their optical, electronic and magnetic properties. [17,18] In this regard, both the heteroatom type, doping position, and doping concentration exhibit significant influence on the electronic band structure and charge carrier concentration of heteroatomdoped GNRs.…”