Supramolecular polymers

Organic electronics is of great fundamental interest in materials science and is also recognized as one of the most promising and competitive markets for industry. In particular, its expansion will be supported by the development of active components being easily processable, flexible, energy friendly, cheap, and compatible with their downscaling towards nano-devices. Recently, the so-called supramolecular electronics has recently been proposed as a promising intermediary-scale approach which rests on the design of electronic components at a length of 5-100 nm, that is comprised between plastic electronics (µm) and molecular electronics (Å). Supramolecular engineering, which programs self-assembly processes under thermodynamic control, but also using nucleation-growth processes, represents a key bottom-up strategy to build and process relatively soft functional objects while introducing “pseudo-crystalline” electroactive domains corresponding to this typical intermediate length scale. Very recently, our group has discovered that properly modified TAA molecules were able to produce self-assemblies thanks to their stacking in columnar fibrils. We have demonstrated that a simple irradiation by visible light of a solution of these molecules in chloroform can generate a non-covalent polymerization leading to supramolecular triarylamine nanowires (STANWs). We have then demonstrated the possibility to take advantage of this triggering capability for probing the conduction properties of the supramolecular assemblies when precisely trapped between pre-patterned metallic electrodes. We have measured a channel conductivity exceeding 5 10³ S.m^-1, and an interface resistance per unit length below 2 10^-4 W.m. Only sorted single-walled metallic carbon nanotubes with ballistic charge transport (that is, exempt of charge scattering) can demonstrate better values. We have now a strong fundamental understanding of these systems, in terms of supramolecular properties and conduction mechanism, and we are developing a number of systems based on this molecular core which shows its generality in terms of structuring properties and outstanding electronic performances.