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Title: Controlled catalyst-transfer polymerization in graphene nanoribbon synthesis
Exercising direct control over the unusual electronic structures arising from quantum confinement effects in graphene nanorib-bons (GNRs) is intimately linked to geometric boundary conditions imposed by the structure of the ribbon. Besides composition and position of substitutional dopant atoms, the symmetry of the unit cell, width, length, and termination of a GNR govern its electronic structure. Here we present a rational design that integrates each of these interdependent variables within a modular bottom-up syn-thesis. Our hybrid chemical approach relies on a catalyst transfer polymerization (CTP) that establishes excellent control over length, width, and end-groups. Complemented by a surface-assisted cy-clodehydrogenation step, uniquely enabled by matrix-assisted di-rect (MAD) transfer protocols, geometry and functional handles encoded in a polymer template are faithfully mapped onto the structure of the corresponding GNR. Bond-resolved scanning tun-nelling microscopy (BRSTM) and spectroscopy (STS) validate the robust correlation between polymer template design and GNR electronic structure.  more » « less
Award ID(s):
2203911
PAR ID:
10515581
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
CHEM
Date Published:
Journal Name:
Chem
Volume:
10
Issue:
2
ISSN:
2451-9294
Page Range / eLocation ID:
675 to 685
Subject(s) / Keyword(s):
graphene nanoribbons (GNRs), Suzuki chain transfer polymerization (SCTP), matrix assisted direct (MAD) transfer, on-surface synthesis (OSS), scanning tunneling microscopy (STM), scanning tunneling spectroscopy (STS)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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