Fluorene-based polymers-preparation and applications

This paper briefly reviews our work on the syntheses and applications of a family of fluorene-based polymers. We have found that fluorene as a monomer offers a number of advantages, the most significant being its ability to impart solubility while maintaining a high degree of delocalization. An improved Pd-catalyzed polymerization procedure has enabled the preparation of a large variety of fluorene homopolymers and copolymers. Unlike PPV and related materials, LED devices with fluorene polymers in a conventional configuration appear to have electrons as the majority carrier and their performance is markedly improved when modified with an appropriate polymeric hole transporting layer. An optimized green-emitting device exhibits very high luminance (10 000 cd m(-2)) at very low bias (< 7 V) and high efficiency (similar to 10 lm W-1), attributable in part to the high hole mobility of fluorene-based polymers. Applications of these materials to other electronic devices, such as field effect transistors and photocells, are in progress.