1. Conjugated Polymers and Carbon Nanotubes for Optoelectronic Applications Liming Dai Department of Polymer Engineering College of Polymer Science and Polymer Engineering The University of Akron, Akron, OH 43325-0301 In close collaboration with Richard A. Vaia AFRL Materials and Manufacturing Directorate Bldg 654, 2941 P St. Wright-Patterson AFB, OH 45433-7750 Collaborative Center for Polymer Photonics Workshop at Akron, April 22-23, 2004

2. Important Discoveries 1977 Conducting Polymer by Heeger, MacDiarmid, Shirakawa 1985 Fullerene C60 Curl, Kroto, Smalley 1990 Conjugated Polymer LEDs by Friend et al. + n e.g. 1991 Carbon Nanotube by Iijima

3. Requirements for Polymers to be Electrically Conducting Just like metals have high conductivity due to the free movement of electrons through their structure, for polymeric systems to be electronically conductive they must possess: a) Charge carriers (Doping) b) An orbit that allows the charge carriers to move (Conjugation) n-doping p-doping

4. Iodine-Induced Conjugation of Polydienes Dai, L. et al, Macromolecules, 1994, 27, 6728.

5. Micropatterning of Conducting Rubbers Dai, L. et al., Macromolecules 1996, 29, 282. (a) (b)

6. The Principle for Polymer Light-Emitting Diodes

7. Colour Tunability of the Light-Emitting Polymers

8. Patterned and Multilayered Light Emissions

9. Confined Space for Colour Tuning B. Winkler et al., J. Mater. Sci. Lett. 1999, 18, 1539.

10. Heeger, et al, Science 1995, 270, 1789. MEH-PPV-C60 blends Conducting Polymer Plastic Solar Cells

11. Iodine-Induced Conjugation of C 60 -Grafted Polydienes Dai, L. et al., J. Phys. Chem. 1995, 99, 17302.

12. Sulfonated C 60 /Dendrimer - Doped Polyaniline Dai, L. et al, J. Phys. Chem. 1998, 102, 4049.

13. Optoelectronic Properties of the Sulfonated C 60 -Doped Polyaniline Film Dai, L, et al., J. Phys Chem. 1998, 102, 4049

14. Optical Limiting by C 60 -Ag Nanocomposites Sun N., et al., Chem. Phys. Lett. 2002, 356, 175. Optical limiting responses to 8ns, 532 nm optical pulses, HDTC60–Ag (square), DT–Ag (circle), and HDTC60 (triangle).

15. Polyaniline Nanotubes Qiu, et al. Macromolecules 2001, 34, 675. PANI-(CNT- OSO 3 H) PANI-(C 60 -OSO 3 H) Wei, et al. Adv. Mater. 2003, 15, 136.

16. Conducting Polymer Micro-/nano-structures Bajpai, et al. Adv. Funct. Mater. 2004, 14, 145.

17. Potential Applications of Conducting Polymer Micro-/nano-structures

18. Carbon Nanotube Electron-Emitting Displays Courtesy of Y. Saito

19. Pyrolytic Growth of Aligned Carbon Nanotubes from Metal-Organic Complex Molecules Huang, et al., J. Phys. Chem. B 1999, 103, 4223.

20. Huang & Dai J. Nanoparticle Res. 2002, 4, 145. The Growth Process for Aligned Carbon Nanotubes