Leclerc, Mario (Université Laval)

Purpose

Conjugated polymers combine the electrical and optical features of inorganic semi-conductors with the mechanical properties unique to polymers. This synergy not only makes these materials useful in existing devices but also creates completely new opportunities. For instance, because conjugated polymers can often be dissolved in common solvents, processing techniques such as inkjet printing, spin coating, and roll-to-roll printing become readily available; thus rendering possible the fabrication of low-cost printed electronic and photonic devices. Such devices include light-emitting diodes, field-effect transistors, chemical and biochemical sensors, photovoltaic and thermoelectric cells, electrochromic windows and the list continues to grow. However, it must be recognized that the development of so-called plastic electronics has been and still remains highly dependent on the availability of robust and versatile building blocks and coupling methods to afford well-defined, efficient, and reproducible conjugated polymers. For this purpose, we propose two extremely innovative projects which should have a major academic and industrial impact. The first project is devoted to the synthesis and characterization of defect-free electroactive and photoactive polymers prepared from novel direct (hetero)arylation reactions. Interestingly, these reactions exhibit several key benefits over well-established polymerization methods: 1) fewer reaction steps; 2) easier purification and; 3) benign acidic by-products. This project should therefore lead to the development of environmentally-benign and low-cost synthetic procedures for the preparation of well-defined conjugated polymers with enhanced performance for organic electronics. The second project is related to the design, synthesis and polymerization of new fluorinated and amide/imide building blocks that should lead to conformationally-locked conjugated polymers with enhanced optical and electrical properties. These studies should not only bring new efficient ambipolar and n-type polymeric materials but should also lead to a change of paradigm about how we design and fabricate plastic solar cells. In short, these cutting-edge research projects will clearly change the way chemists prepare conjugated polymers and how plastic solar cells are designed. Efficient, low-cost and environmentally benign polymerization methods will be developed for the preparation of defect-free and high-performance conjugated polymers. All of these studies in polymer chemistry will therefore significantly enlarge the possibilities for the applications of conjugated organic materials while contributing to a multidisciplinary formation of highly qualified personnel.