Suchergebnisse

Graphene nanoribbons (GNRs) and their derivatives attract growing attention due to their excellent electronic and magnetic properties as well as the fine-tuning of such properties that can be obtained by heteroatom substitution and/or edge morphology modification. Here, we introduce graphene nanoribbon derivatives—organometallic hybrids with gold atoms incorporated between the carbon skeleton and side Cl atoms. We show that narrow chlorinated 5-AGNROHs (armchair graphene nanoribbon organometallic hybrids) can be fabricated by on-surface polymerization with omission of the cyclodehydrogenation reaction by a proper choice of tailored molecular precursors. Finally, we describe a route to exchange chlorine atoms connected through gold atoms to the carbon skeleton by hydrogen atom treatment. This is achieved directly on the surface, resulting in perfect unsubstituted hydrogen-terminated GNRs. This will be beneficial in the molecule on-surface processing when the preparation of final unsubstituted hydrocarbon structure is desired. ; This work was supported by the National Science Center, Poland (2019/35/B/ST5/02666), and the EU Project PAMS (610446). A.G.L., D.S.P., and P.B. acknowledge the Spanish Agencia Estatal de Investigación (Grants MAT2016-78293-C6-4-R, PID2019-107338RB-C66, and FIS2017-83780-P), Dep. Educación of the Basque Government and UPV/EHU (Grant IT-756-13), and the European Union (EU) through Horizon 2020 (FET-Open project SPRING Grant 863098) for support. ; Peer reviewed

The synthesis of porous nanographenes is a challenging task for solution chemistry, and thus, on-surface synthesis provides an alternative approach. Here, we report the synthesis of a triporous nanographene with 102 sp2 carbon atoms by combining solution and surface chemistry. The carbon skeleton was obtained by Pd-catalyzed cyclotrimerization of arynes in solution, while planarization of the molecule was achieved through two hierarchically organized on-surface cyclodehydrogenation reactions, intra- and inter-blade. Remarkably, the three non-planar [14]annulene pores of this nanographene further evolved at higher temperatures showing interesting intra-porous on-surface reactivity ; We acknowledge financial support from the National Science Center, Poland (2017/26/E/ST3/00855), Agencia Estatal de Investigación (MAT2016-78293-C6-3-R and CTQ2016-78157-R), Xunta de Galicia (Centro singular de investigación de Galicia, accreditation 2016–2019, ED431G/09) and Fondo Europeo de Desarrollo Regional (FEDER). IP thanks Xunta de Galicia and the European Union (European Social Fund, ESF) for awarding a pre-doctoral fellowship ; SI