Nanostructured graphene has been widely studied in recent years due to the tunability of its electronic properties and its associated interest for a variety of fields, such as nanoelectronics and spintronics. However, many of the graphene nanostructures of technological interest are synthesized under ultrahigh vacuum, and their limited stability as they are brought out of such an inert environment may compromise their applicability. In this study, a combination of bond-resolving scanning probe microscopy (BR-SPM), along with theoretical calculations, has been employed to study (3,1)-chiral graphene nanoribbons [(3,1)-chGNRs] that were synthesized on a Au(111) surface and then exposed to oxidizing environments. Exposure to the ambient atmosphere, along with the required annealing treatment to desorb a sufficiently large fraction of contaminants to allow for its postexposure analysis by BR-SPM, revealed a significant oxidation of the ribbons, with a dramatically disruptive effect on their electronic properties. More controlled experiments avoiding high temperatures and exposing the ribbons only to low pressures of pure oxygen show that also under these more gentle conditions the ribbons are oxidized. From these results, we obtain additional insights into the preferential reaction sites and the nature of the main defects that are caused by oxygen. We conclude that graphene nanoribbons with zigzag edge segments require forms of protection before they can be used in or transferred through ambient conditions.

Centro de Física de Materiales 20018 San Sebastián Spain

Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares and Departamento de Química Orgánica Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain

Donostia International Physics Center 20018 San Sebastián Spain

Ikerbasque Basque Foundation for Science 48013 Bilbao Spain

Institute of Physics Czech Academy of Sciences 16200 Prague Czech Republic

Citace poskytuje Crossref.org

Circumventing the stability problems of graphene nanoribbon zigzag edges