On‐Surface Synthesis of Edge‐Extended Zigzag Graphene Nanoribbons

Abstract

Graphene nanoribbons (GNRs) have gained significant attention in nanoelectronics due to their potential for precise tuning of electronic properties through variations in edge structure and ribbon width. However, the synthesis of GNRs with highly sought‐after zigzag edges (ZGNRs), critical for spintronics and quantum information technologies, remains challenging. In this study, we present a design motif for synthesizing a novel class of GNRs termed edge‐extended ZGNRs. This motif enables the controlled incorporation of edge extensions along the zigzag edges at regular intervals. We successfully demonstrate the synthesis of a specific GNR instance—a 3‐zigzag‐rows‐wide ZGNR—with bisanthene units fused to the zigzag edges on alternating sides of the ribbon axis. The resulting edge‐extended 3‐ZGNR is comprehensively characterized for its chemical structure and electronic properties using scanning probe techniques, complemented by density functional theory calculations. The design motif showcased here opens up new possibilities for synthesizing a diverse range of edge‐extended ZGNRs, expanding the structural landscape of GNRs and facilitating the exploration of their structure‐dependent electronic properties.This article is protected by copyright. All rights reserved

On-Surface Synthesis of Anthracene-Fused Zigzag Graphene Nanoribbons from 2,7-Dibromo-9,9′-bianthryl Reveals Unexpected Ring Rearrangements

“…Zigzag GNRs (ZGNRs) can host spin-polarized states localized on their edges and are thus considered promising for spintronic device applications. ,, However, experimental reports on ZGNRs are still scarce in literature. − To this end, we have recently proposed a new design motif for the synthesis of edge-extended ZGNRs, obtaining bisanthene-fused ZGNRs . Based on this motif, 2,7-dibromo-9,9′-bianthryl (2,7-DBBA 3 ) can be considered to furnish anthracene-fused N = 3 ZGNRs, which we name as 3-ZGNR-E­(Anthracene, 7) (see ref . for the definition of the nomenclature, where E stands for “Extended” and 7 indicates the periodicity of the fused units in terms of the axial unit vector of the ZGNR; hereafter called 3-ZGNR-EA for clarity).…”

“… 32 − 36 To this end, we have recently proposed a new design motif for the synthesis of edge-extended ZGNRs, obtaining bisanthene-fused ZGNRs. 33 Based on this motif, 2,7-dibromo-9,9′-bianthryl (2,7-DBBA 3 ) can be considered to furnish anthracene-fused N = 3 ZGNRs, which we name as 3-ZGNR-E(Anthracene, 7) (see ref ( 33 ). for the definition of the nomenclature, where E stands for “Extended” and 7 indicates the periodicity of the fused units in terms of the axial unit vector of the ZGNR; hereafter called 3-ZGNR-EA for clarity).…”

Exploring Spin Distribution and Electronic Properties in FeN4-Graphene Catalysts with Edge Terminations

“…These structures hold promise for applications in spintronics and quantum information technologies. However, synthesizing magnetic monohydrated ZGNRs remains challenging [ 2 , 3 ], leading to extensive theoretical [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ] and experimental efforts [ 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. The objective is to understand, modify, and control the spin-density distributions in nanostructured graphene.…”

Electronic Decoupling and Hole-Doping of Graphene Nanoribbons on Metal Substrates by Chloride Intercalation

“…However, the carbon nanomaterials thus synthesized are found adsorbed on these catalytic surfaces, which can obscure the intrinsic electronic properties of the synthesized materials. 4 Moreover, the substrate also determines the Fermi energy of the adsorbed nanomaterials. This rules out any possibility for gating the nanomaterials without first electronically decoupling them from the metal.…”

“…Carefully designed molecular precursors can be made to undergo selective surface-catalyzed reactions to yield atomically precise carbon nanomaterials. − The reactions that this so-called on-surface synthesis strategy relies on are best catalyzed by metallic surfaces, in particular, Au(111). However, the carbon nanomaterials thus synthesized are found adsorbed on these catalytic surfaces, which can obscure the intrinsic electronic properties of the synthesized materials . Moreover, the substrate also determines the Fermi energy of the adsorbed nanomaterials.…”