Extended monolayer of cyano-ended oligo(para-phenylenes) at the air/HOPG interface investigated by high-resolution AFM.

The formation of functional networks on surfaces is one of the main challenges in the field of nanotechnologies. In this paper, we shall propose a very simple process which can be used to achieve the formation of extended monolayer of functional oligo(para-phenylenes) molecules at the air/graphite interface. By developing a convergent strategy, we successfully achieved the synthesis of oligo(para-phenylenes) molecules with a tuneable length. The photophysical properties of these new oligomers were characterized by UV-vis absorption and fluorescence spectroscopy. Deposition of these molecules by a simple spin-coating process on a highly oriented pyrolytic graphite (HOPG) surface leads to the formation of extended monolayered 2D networks. These networks were characterized by atomic force microscopy experiments under ambient conditions with submolecular resolution thus providing the adsorption model of these molecules on an HOPG surface.