Carbon nanostructures, such as nanotubes and graphenes, represent a very promising class of new materials in the field of nanotechnology. In principle, graphenes could be obtained following a bottom-up approach by synthesizing large polycyclic aromatic hydrocarbons (nanographenes) [1] starting from suitable precursors. Their subsequent intermolecular condensation into progressively more extended structures can produce macroscopic graphene films.
Amongst the polycyclic aromatic hydrocarbons, Corannulene is a bowl-shaped species recalling the fullerene surface. It is particularly intriguing, for its unique redox and luminescent properties, to develop new materials. The electrochemical reduction processes have been reinvestigated in our lab over a large range of experimental conditions [2].
Concerning the oxidation, so far scarsely investigated, reports only a process which is completely irreversible and it brings about a rapid fouling and passivation of the electrode surface [3]. The adoption of suitable ultra-dry solvents and electrolytes, with very high oxidation resistance and low nucleophilicity, allowed to explore the reactivity of the electrogenerated corannulene carbocations.
The interesting redox, spectroelectrochemical, luminescence and electrochemiluminesce properties [4] of corannulene and derivative species, together with the structure of their electrochemically generated films, will be discussed.
[1] Müllen, K.J. et al. J. Am. Chem. Soc. 2004, 126, 3139.
[2] Bruno, C. et al. J. Phys. Chem. B 2009, 113, 1954.
[3] Valenti, G. et al. J. Phys. Chem. C 2010, 114, 19467.
Dipartimento di Chimica “G. Ciamician” Università di Bologna