Recent years have witnessed fast advancements in the research on graphene,
which is one of the most active fields in condensed matter physics,
chemistry and materials science. The rising interest of the scientific community
in graphene, motivated by its fascinating properties and wide range
of potential applications, has triggered substantial interest also on other
two-dimensional (2D) atomic crystals, and particularly on hexagonal boron
nitride (h-BN). In spite of much effort, a number of challenges still awaits
the scientific community before the full potential of 2D atomic crystals can
be exploited, such as the development of reliable methods for the growth
of high-quality graphene and h-BN single layers or the possibility to tune
the graphene electronic structure.
The research activity I have been pursuing faces these requirements by
focusing on the growth of graphene and h-BN on transition metal surfaces
– which appears as the most direct route towards a scalable production of
single layers with low concentration of defects – and the investigation of
fundamental properties related to the presence of the metal support, but
also tackles issues which have a direct link to the fabrication of carbonbased
devices.
In this regard, one of the first targets has been to shed light on the morphology
and the electronic structure of h-BN on Ir(111), and to improve the
growth strategy for the synthesis of high-quality h-BN layers.
I have subsequently turned my attention to the fine tuning of graphene
electronic properties by tailoring the graphene-substrate interaction
through intercalation of foreign atoms at the metal interface. This was investigated
in the extreme situations of weak (Ir) and strong (Ru) coupling
of graphene with the metal support.
I have also focused on an aspect which is related to a specific technological
issue, that is, the development of an approach for the direct synthesis
of graphene on insulating oxide layers.
Lastly, the structural geometry of single layer graphene functionalized
with nitrogen atoms, which is considered as one of the most promising
approaches to manipulate graphene chemistry and induce n-doping, was
also addressed.
The combined use of several surface science experimental techniques
has been proved to be of a powerful approach to achieve the targets of this
project, having given access to the understanding of different properties of
the systems under investigation.
