Titre : Controlling Order in Self-Assembled Molecular Thin Films

Endroit: Salle G-615, Pavillon Roger-Gaudry

Résumé:The development of new molecules and polymers is necessary
to fabricate advanced organic electronics, energy storage devices, and
nanofluidics. While molecular structures play a key role in material property
determination, the final device’s performance is mainly limited by the structural
order of the material. We investigate the importance of structural order in a
diverse set of thin-film materials. Using short self-assembled oligothiophenes,
we demonstrated that ordered films can have an extraordinary increase in
tunneling probability with increasing molecular chain length.

Using thin films of long-backbone P3HT, we showed that optimal carrier
mobility can be achieved by the application of shear polymer flow,
demonstrating the importance of processing strategies. We also showed
that ordered monolayers of the photosynthetic protein Photosystem I can be
applied to develop electrical diodes and photovoltaic cells. We demonstrated
that the self-assembly of block co-polymer micelles onto 2D materials is a
promising strategy for their surface nanopatterning, leading to an increase
of 2D sheet surface area for improving capacitance properties. However,
controlling the order between neighboring sheets in the final device remains
challenging. Controlling interactions between 2D sheets could improve
structural order and device performance.