A new class of nanostructured supramolecular organic semiconductors based on intertwined multi-lamellar co-assemblies in π-conjugated liquid-crystalline side-chain polymers
Résumé
The control of both the mesoscopic and nanoscale organizations within thin semiconducting films is a key issue for the improvement of the charge transport properties and the achievement of high charge-carrier mobilities. In this review, we summarized our previous work devoted to the design and synthesis of a new type of side-chain liquid crystal π-conjugated polymeric system associating regioregular poly(3-alkylthiophene) backbones with laterally pending π-conjugated mesogenic groups. Depending on the nature of the mesogenic side groups, this specific polymer design permits the production of lamellocolumnar or lamellolamellar mesophases, resulting in an intertwined co-assembly either of lamellae and columns or of two different types of lamellae. These optimized polymeric architectures based on two chemically different moieties constitute an interesting basis for the design of novel self-organized complex semiconducting materials. By associating with judicious side groups such as n-type entities, we demonstrated that this simple and versatile strategy can produce distinct conductive channels for both types of charge carrier and can lead to a new class of supramolecular ambipolar materials that is easily processable and potentially suitable for electronic and optoelectronic applications.