Xiushang Xu^1,2, Marco Di Giovannantonio^3,4, José I. Urgel^3,5, Carlo A. Pignedoli^3*, Pascal Ruffieux³, Klaus Müllen^1,6, Roman Fasel³, Akimitsu Narita^1,2

1 Max Planck Institute for Polymer Research, 55128 Mainz, Germany.

2 Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan

3 Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, 8600 Dübendorf, Switzerland

4 Present address: Istituto di Struttura della Materia-CNR (ISM-CNR), via Fosso del Cavaliere 100, 00133 Roma, Italy

5 Present address: IMDEA Nanoscience, C/Faraday 9, Campus de Cantoblanco, 28049 Madrid, Spain

6 Institute of Physical Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128 Mainz, Germany

* Corresponding authors emails: carlo.pignedoli@empa.ch

DOI10.24435/materialscloud:xj-bb [version v1]

Publication date: Apr 15, 2021

How to cite this record

Xiushang Xu, Marco Di Giovannantonio, José I. Urgel, Carlo A. Pignedoli, Pascal Ruffieux, Klaus Müllen, Roman Fasel, Akimitsu Narita, On-surface activation of benzylic C-H bonds for the synthesis of pentagon-fused graphene nanoribbons, Materials Cloud Archive 2021.63 (2021), doi: 10.24435/materialscloud:xj-bb.

Description

In the record we provide the inputs and outputs for the calculations that support our recent results in the synthesis of pentagon-fused graphene nanoribbons (GNRs). GNRs have potential for applications in electronic devices. A key issue, thereby, is the fine-tuning of their electronic characteristics, which can be achieved through subtle structural modifications. These are not limited to the conventional armchair, zigzag, and cove edges, but also possible through incorporation of non-hexagonal rings. On-surface synthesis enables the fabrication and visualization of GNRs with atomically precise chemical structures, but strategies for the incorporation of non-hexagonal rings have been underexplored. In the manuscript, we describe the on-surface synthesis of armchair-edged GNRs with incorporated five-membered rings through the C-H activation and cyclization of benzylic methyl groups. ortho-Tolyl-substituted dibromobianthryl was employed as the precursor monomer, and visualization of the resulting structures after annealing at 300 °C on a gold surface by high-resolution noncontact atomic force microscopy clearly revealed the formation of methylene-bridged pentagons at the GNR edges. These persisted after annealing at 340 °C, along with a few fully conjugated pentagons having singly-hydrogenated apexes. The benzylic methyl groups could also migrate or cleave-off, resulting in defects lacking the five-membered rings. Moreover, unexpected and unique structural rearrangements, including the formation of embedded heptagons, were observed, providing novel insights into the on-surface reactions en route to functional carbon nanomaterials.

Materials Cloud sections using this data

Files

File name	Size	Description
Readme.txt MD5md5:87be03b5fcee607eb57b6772dc392df4	520 Bytes	Readme file describing the content of the record
calculations.aiida MD5md5:471b235b6040ef9371ef1bd09fcc1af9	260.2 MiB	AiiDA archive file containing all nodes of the calculations

License

Files and data are licensed under the terms of the following license: Creative Commons Attribution 4.0 International.
Metadata, except for email addresses, are licensed under the Creative Commons Attribution Share-Alike 4.0 International license.

External references

Keywords

MARVEL/DD3 graphene nanoribbons on surface synthesis Graphene Flagship ab initio calculations carbon based nanomaterials