Carbon nanostructures with zigzag edges exhibit unique properties-such as localized electronic states and spins-with exciting potential applications. Such nanostructures however are generally synthesized under vacuum because their zigzag edges are unstable under ambient conditions: a barrier that must be surmounted to achieve their scalable integration into devices for practical purposes. Here we show two chemical protection/deprotection strategies, demonstrated on labile, air-sensitive chiral graphene nanoribbons. Upon hydrogenation, the chiral graphene nanoribbons survive exposure to air, after which they are easily converted back to their original structure by annealing. We also approach the problem from another angle by synthesizing a form of the chiral graphene nanoribbons that is functionalized with ketone side groups. This oxidized form is chemically stable and can be converted to the pristine hydrocarbon form by hydrogenation and annealing. In both cases, the deprotected chiral graphene nanoribbons regain electronic properties similar to those of the pristine nanoribbons. We believe both approaches may be extended to other graphene nanoribbons and carbon-based nanostructures.

Centro de Física de Materiales CSIC UPV EHU San Sebastián Spain

Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares and Departamento de Química Orgánica Universidade de Santiago de Compostela Santiago de Compostela Spain

Donostia International Physics Center San Sebastián Spain

Faculty of Nuclear Sciences and Physical Engineering Czech Technical University Prague Prague Czech Republic

Ikerbasque Basque Foundation for Science Bilbao Spain

Institute of Physics Czech Academy of Sciences Prague Czech Republic

Nanomaterials and Nanotechnology Research Center CSIC UNIOVI PA El Entrego Spain

Regional Centre of Advanced Technologies and Materials Czech Advanced Technology and Research Institute Palacký University Olomouc Olomouc Czech Republic

Erratum v

Nat Chem. 2022 Dec;14(12):1471-1473. doi: 10.1038/s41557-022-01105-w. PubMed

Erratum v

Nat Chem. 2025 Feb;17(2):299. doi: 10.1038/s41557-023-01324-9. PubMed

Zobrazit více v PubMed

Corso, M., Carbonell-Sanromà, E. & de Oteyza, D. G. in On-Surface Synthesis II 113–152 (Springer, 2018).

Yano Y, Mitoma N, Ito H, Itami K. A quest for structurally uniform graphene nanoribbons: synthesis, properties, and applications. J. Org. Chem. 2020;85:4–33. doi: 10.1021/acs.joc.9b02814. PubMed DOI

Zhou X, Yu G. Modified engineering of graphene nanoribbons prepared via on‐surface synthesis. Adv. Mater. 2020;32:1905957. doi: 10.1002/adma.201905957. PubMed DOI

Chen Y-C, et al. Molecular bandgap engineering of bottom-up synthesized graphene nanoribbon heterojunctions. Nat. Nanotechnol. 2015;10:156–160. doi: 10.1038/nnano.2014.307. PubMed DOI

Rizzo DJ, et al. Topological band engineering of graphene nanoribbons. Nature. 2018;560:204–208. doi: 10.1038/s41586-018-0376-8. PubMed DOI

Gröning O, et al. Engineering of robust topological quantum phases in graphene nanoribbons. Nature. 2018;560:209–213. doi: 10.1038/s41586-018-0375-9. PubMed DOI

Li J, et al. Survival of spin state in magnetic porphyrins contacted by graphene nanoribbons. Sci. Adv. 2018;4:eaaq0582. doi: 10.1126/sciadv.aaq0582. PubMed DOI PMC

Li J, et al. Electrically addressing the spin of a magnetic porphyrin through covalently connected graphene electrodes. Nano Lett. 2019;19:3288–3294. doi: 10.1021/acs.nanolett.9b00883. PubMed DOI

Mateo LM, et al. On‐surface synthesis and characterization of triply fused porphyrin–graphene nanoribbon hybrids. Angew. Chem. Int. Ed. 2020;59:1334–1339. doi: 10.1002/anie.201913024. PubMed DOI

Yazyev OV. A guide to the design of electronic properties of graphene nanoribbons. Acc. Chem. Res. 2013;46:2319–2328. doi: 10.1021/ar3001487. PubMed DOI

Yazyev OV. Emergence of magnetism in graphene materials and nanostructures. Rep. Prog. Phys. 2010;73:056501. doi: 10.1088/0034-4885/73/5/056501. DOI

Fairbrother A, et al. High vacuum synthesis and ambient stability of bottom-up graphene nanoribbons. Nanoscale. 2017;9:2785–2792. doi: 10.1039/C6NR08975E. PubMed DOI

Ma C, et al. Oxidization stability of atomically precise graphene nanoribbons. Phys. Rev. Mater. 2018;2:014006. doi: 10.1103/PhysRevMaterials.2.014006. DOI

Berdonces-Layunta A, et al. Chemical stability of (3,1)-chiral graphene nanoribbons. ACS Nano. 2021;15:5610–5617. doi: 10.1021/acsnano.1c00695. PubMed DOI

Yoon K-Y, Dong G. Liquid-phase bottom-up synthesis of graphene nanoribbons. Mater. Chem. Front. 2020;4:29–45. doi: 10.1039/C9QM00519F. DOI

Narita A, Wang X-Y, Feng X, Müllen K. New advances in nanographene chemistry. Chem. Soc. Rev. 2015;44:6616–6643. doi: 10.1039/C5CS00183H. PubMed DOI

Kan E, Li Z, Yang J, Hou JG. Half-metallicity in edge-modified zigzag graphene nanoribbons. J. Am. Chem. Soc. 2008;130:4224–4225. doi: 10.1021/ja710407t. PubMed DOI

Carbonell-Sanromà E, et al. Doping of graphene nanoribbons via functional group edge modification. ACS Nano. 2017;11:7355–7361. doi: 10.1021/acsnano.7b03522. PubMed DOI

Li J, et al. Band depopulation of graphene nanoribbons induced by chemical gating with amino groups. ACS Nano. 2020;14:1895–1901. doi: 10.1021/acsnano.9b08162. PubMed DOI

Anthony JE. The larger acenes: versatile organic semiconductors. Angew. Chem. Int. Ed. 2008;47:452–483. doi: 10.1002/anie.200604045. PubMed DOI

Greene, T. W. & Wuts, P. G. M. Protective Groups in Organic Synthesis (Wiley, 1999).

Chia C-I, Crespi VH. Stabilizing the zigzag edge: graphene nanoribbons with sterically constrained terminations. Phys. Rev. Lett. 2012;109:076802. doi: 10.1103/PhysRevLett.109.076802. PubMed DOI

Li Y, Zhou Z, Cabrera CR, Chen Z. Preserving the edge magnetism of zigzag graphene nanoribbons by ethylene termination: insight by Clar’s rule. Sci. Rep. 2013;3:2030. doi: 10.1038/srep02030. PubMed DOI PMC

Sun Z, et al. Dibenzoheptazethrene isomers with different biradical characters: an exercise of Clar’s aromatic sextet rule in singlet biradicaloids. J. Am. Chem. Soc. 2013;135:18229–18236. doi: 10.1021/ja410279j. PubMed DOI

Clair S, de Oteyza DG. Controlling a chemical coupling reaction on a surface: tools and strategies for on-surface synthesis. Chem. Rev. 2019;119:4717–4776. doi: 10.1021/acs.chemrev.8b00601. PubMed DOI PMC

Wang T, Zhu J. Confined on-surface organic synthesis: strategies and mechanisms. Surf. Sci. Rep. 2019;74:97–140. doi: 10.1016/j.surfrep.2019.05.001. DOI

Held PA, Fuchs H, Studer A. Covalent-bond formation via on-surface chemistry. Chem. Eur. J. 2017;23:5874–5892. doi: 10.1002/chem.201604047. PubMed DOI

Song S, et al. On-surface synthesis of graphene nanostructures with π-magnetism. Chem. Soc. Rev. 2021;50:3238–3262. doi: 10.1039/D0CS01060J. PubMed DOI

Liu J, Feng X. Synthetic tailoring of graphene nanostructures with zigzag‐edged topologies: progress and perspectives. Angew. Chem. Int. Ed. 2020;59:23386–23401. doi: 10.1002/anie.202008838. PubMed DOI PMC

Li J, et al. Single spin localization and manipulation in graphene open-shell nanostructures. Nat. Commun. 2019;10:200. doi: 10.1038/s41467-018-08060-6. PubMed DOI PMC

Mishra S, et al. Topological frustration induces unconventional magnetism in a nanographene. Nat. Nanotechnol. 2020;15:22–28. doi: 10.1038/s41565-019-0577-9. PubMed DOI

Zuzak R, et al. On-surface synthesis of chlorinated narrow graphene nanoribbon organometallic hybrids. J. Phys. Chem. Lett. 2020;11:10290–10297. doi: 10.1021/acs.jpclett.0c03134. PubMed DOI PMC

Zuzak R, Jančařík A, Gourdon A, Szymonski M, Godlewski S. On-surface synthesis with atomic hydrogen. ACS Nano. 2020;14:13316–13323. doi: 10.1021/acsnano.0c05160. PubMed DOI PMC

de Oteyza DG, et al. Substrate-independent growth of atomically precise chiral graphene nanoribbons. ACS Nano. 2016;10:9000–9008. doi: 10.1021/acsnano.6b05269. PubMed DOI PMC

Merino-Díez N, et al. Transferring axial molecular chirality through a sequence of on-surface reactions. Chem. Sci. 2020;11:5441–5446. doi: 10.1039/D0SC01653E. PubMed DOI PMC

Merino-Díez N, et al. Unraveling the electronic structure of narrow atomically-precise chiral graphene nanoribbons. J. Phys. Chem. Lett. 2018;9:25–30. doi: 10.1021/acs.jpclett.7b02767. PubMed DOI PMC

Li J, et al. Topological phase transition in chiral graphene nanoribbons: from edge bands to end states. Nat. Commun. 2021;12:5538. doi: 10.1038/s41467-021-25688-z. PubMed DOI PMC

Konishi A, Kubo T. Benzenoid quinodimethanes. Top. Curr. Chem. 2017;375:83. doi: 10.1007/s41061-017-0171-2. PubMed DOI

Clar, E. The Aromatic Sextet (J. Wiley, 1972).

Mohammed MSG, et al. Electronic decoupling of polyacenes from the underlying metal substrate by sp3 carbon atoms. Commun. Phys. 2020;3:159. doi: 10.1038/s42005-020-00425-y. DOI

Merino-Díez N, et al. Width-dependent band gap in armchair graphene nanoribbons reveals Fermi level pinning on Au(111) ACS Nano. 2017;11:11661–11668. doi: 10.1021/acsnano.7b06765. PubMed DOI PMC

Endo O, Nakamura M, Amemiya K, Ozaki H. Graphene nanoribbons formed from n-alkane by thermal dehydrogenation on Au(111) surface. Surf. Sci. 2015;635:44–48. doi: 10.1016/j.susc.2014.12.005. DOI

Wang T, et al. Magnetic interactions between radical pairs in chiral graphene nanoribbons. Nano Lett. 2022;22:164–171. doi: 10.1021/acs.nanolett.1c03578. PubMed DOI

Itoh T, Matsuno M, Kamiya E, Hirai K, Tomioka H. Preparation of copper ion complexes of sterically congested diaryldiazomethanes having a pyridine ligand and characterization of their photoproducts. J. Am. Chem. Soc. 2005;127:7078–7093. doi: 10.1021/ja0424225. PubMed DOI

Di Giovannantonio M, et al. On-surface growth dynamics of graphene nanoribbons: the role of halogen functionalization. ACS Nano. 2018;12:74–81. doi: 10.1021/acsnano.7b07077. PubMed DOI

Berdonces-Layunta A, et al. Order from a mess: the growth of 5-armchair graphene nanoribbons. ACS Nano. 2021;15:16552–16561. doi: 10.1021/acsnano.1c06226. PubMed DOI

Blum V, et al. Ab initio molecular simulations with numeric atom-centered orbitals. Comput. Phys. Commun. 2009;180:2175–2196. doi: 10.1016/j.cpc.2009.06.022. DOI

Becke AD. Density‐functional thermochemistry. III. The role of exact exchange. J. Chem. Phys. 1993;98:5648–5652. doi: 10.1063/1.464913. DOI

Perdew JP, Burke K, Ernzerhof M. Generalized gradient approximation made simple. Phys. Rev. Lett. 1996;77:3865–3868. doi: 10.1103/PhysRevLett.77.3865. PubMed DOI

Tkatchenko A, Scheffler M. Accurate molecular van der Waals interactions from ground-state electron density and free-atom reference data. Phys. Rev. Lett. 2009;102:073005. doi: 10.1103/PhysRevLett.102.073005. PubMed DOI

Monkhorst HJ, Pack JD. Special points for Brillouin-zone integrations. Phys. Rev. B. 1976;13:5188–5192. doi: 10.1103/PhysRevB.13.5188. DOI

Lewis JP, et al. Advances and applications in the FIREBALL ab initio tight-binding molecular-dynamics formalism. Phys. Status Solidi B. 2011;248:1989–2007. doi: 10.1002/pssb.201147259. DOI

Hapala, P. et al. Mechanism of high-resolution STM/AFM imaging with functionalized tips. Phys. Rev. B90, 085421 (2014).

Krejčí O, Hapala P, Ondráček M, Jelínek P. Principles and simulations of high-resolution STM imaging with a flexible tip apex. Phys. Rev. B. 2017;95:045407. doi: 10.1103/PhysRevB.95.045407. DOI

Spinons in nanographene spin chains