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arXiv · 2006.13444

Well-defined sub-nanometer graphene ribbons synthesized inside carbon nanotubes

Hans Kuzmany·Lei Shi·Miles Martinati·Sofie Cambré·Wim Wenseleers·Jenő Kürti·János Koltai·Gergő Kukucska·Kecheng Cao·Ute Kaiser·Takeshi Saito·Thomas Pichler
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Abstract

Graphene nanoribbons with sub-nanometer widths are extremely interesting for nanoscale electronics and devices as they combine the unusual transport properties of graphene with the opening of a band gap due to quantum confinement in the lateral dimension. Strong research efforts are presently paid to grow such nanoribbons. Here we show the synthesis of 6- and 7-armchair graphene nanoribbons, with widths of 0.61 and 0.74 nm, and excitonic gaps of 1.83 and 2.18 eV, by high-temperature vacuum annealing of ferrocene molecules inside single-walled carbon nanotubes. The encapsulation of the so-obtained graphene nanoribbons is proved by atomic resolution electron microscopy, while their assignment is provided by a combination of an extensive wavelength-dependent Raman scattering characterization and quantum-chemical calculations. These findings enable a facile and scalable approach leading to the controlled growth and detailed analysis of well-defined sub-nanometer graphene nanoribbons.

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Hans Kuzmany, Lei Shi, Miles Martinati, Sofie Cambré, Wim Wenseleers, Jenő Kürti, János Koltai, Gergő Kukucska, Kecheng Cao, Ute Kaiser, Takeshi Saito, Thomas Pichler. 2020-06-24. Well-defined sub-nanometer graphene ribbons synthesized inside carbon nanotubes. https://arxiv.org/abs/2006.13444

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