Our research focuses on the realization of nanometer-size structures supported by solid surfaces by taking advantage of the spontaneous organization of matter (self-assembly processes).

 

Among the possible routes, we study the supramolecular assemblies formed on a well defined surface after vapor deposition of polycyclic organic molecules. When properly functionalized at their periphery, these molecules (phthalocyanines, perylene, ...) are able to form various kind of intermolecular bonds. The most common approach is to take use of hydrogen bonds between complementary molecules. We can realize extended supramolecular nano-architectures, the structure of which results from the configuration of the terminal groups and the molecule-substrate interactions. Another more recent approach consists in creating two-dimensional networks by initiating chemical reactions directly on a surface. Here we aim at forming strong bonds, which may be purely covalent or based on metal coordination. Moreover, the particular reaction system involved must allow for a periodic repetition of the motif that extends to the whole surface to create a two-dimensional single polymer sheet. Such nanostructured systems can serve as a basis for the development of new functional materials (nano-electronics, opto-electronics, sensors, ...).

 

The growth and self-assembly mechanisms are investigated and characterized in UHV by LEED-STM on metal surfaces and by non-contact AFM and low-current LEED on insulating surfaces. Direct photoemission spectroscopy (XPS / UPS) and inverse photoemission (IPE) are implemented to measure the electronic properties of these organic films.

 

Another approach to create nanostructured molecular monolayers through co-adsorption on a solid surface from the liquid phase is also studied (at ISEN-Toulon). The formation of nano-domains is achieved by phase separation between two types of co-adsorbed molecules (alkyltrichlorosilanes) of different lengths. This allows considering the implementation of non-lithographic nano-components by selective functionalization of these nano-domains (nano-transistors, nano-light emitting diodes, memory, sensors ...). On the Toulon campus is also implemented a novel technique that couples AFM microscopy with Raman spectroscopy to explore optical properties at the nanoscale.

More information:
Self-organized growth of molecular arrays at surfaces
Porte L.; Abel M.; Amsalem P.; Bocquet F.; Bocquet F.C.; Chevallier V.; Clair S., Delafosse G.; Desbief S.; Gadenne V.; Giovanelli L.; Koudia M.; Ksari Y.; Loppacher C.; Merlen A.; Nony L.; Ourdjini O.; Patrone L.; Pawlak R.; Romann J.; Valmalette J.-C.; Themlin J.-M.
International Journal of Nanotechnology 9, 325 (2012)

 

• V. Oison and M. Sassi, from Jean-Marc Debierre’s group, IM2NP
• Wenceslas Rahajandraibe from H.Barthélémy’s group, IM2NP
• Dr. Thilo Glatzel, from Ernst Meyer’s group. Department of Physics of the University of Basel , Switzerland .
• Prof. Adam Foster, Department of Physics, Tampere University of Technology , Finland
• CEMES ( Centre d’élaboration de matériaux et d’études structurales ), Université Paul Sabatier, Toulouse
• IEMN (Institut d’Electronique de Microélectronique et de Nanotechnologie) à Villeneuve d’Ascq, équipe Nanostructures et Composants Moléculaires)
• LACCSC - ECE (Ecole Centrale d’Electronique) Paris
• IMRAM, Université de Tohoku (Japon)
• Synchrotron ELETTRA de Trieste, Ligne "SuperESCA"

Projects funded by the ANR :

• Functionalized molecules on SiC surface: from a single molecule to a monolayer (MolSiC) – ANR-08-NANO-030-02
• Cantilevers en carbure de silicium à piézorésistivité métallique pour AFM dynamique à très haute fréquence (NanoSens) – ANR-08-NANO-017
• CRISTALMOL2D – ANR-PNANO 06-0251