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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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Prof. John Reynolds, University of Florida
Î -Conjugated Polymers: Pushing the Limits Using Chemistry
Special Seminar
Conjugated polymers provide a unique encompassing set of structurally tunable optical, electronic transport, and redox properties that allows their present and potential use in a host of applications which span nearly metallic materials, field effect transistors, light emitting diodes, solar cells and photodetectors, chem/bio-sensors, electrochromism, along with batteries and supercapacitors. Each of these properties can be controlled by repeat unit, macromolecular, and solid-state structure which are all dependent on the chemical identity of each system. In this presentation, we will explore how chemistry enables the creation of new polymers where a specific property is pushed towards its limit. Dioxypyrrole-based polymers provide the most electron rich, and most easily oxidized, conjugated polymer family as desired for stable conductivity and long lived redox switching.1 The flexible synthetic chemistry of dioxythiophene-based polymers has allowed us to complete the color palette of vibrantly colored to transmissive switching electrochromes of any color, including black.2,3 Two band absorption induced by the incorporation of a donor-acceptor-donor triad in the polymer chain induces long wavelength light collection well into the near infrared for photovoltaic devices,4 and even into the mid infrared as desired for photodetectors.5 Accessing highly solution processble conjugated polymers allows us to spray- and print-process for a response or interaction over large-areas and on flexible substrates. These examples serve to demonstrate the approach the chemist uses in conjugated polymer research, and provides insight for making great strides in the future.
1Walczak, R. M.; Reynolds, J. R. Adv. Mater. 2006, 18, 1121-1131. âPoly(3,4-alkylenedioxypyrroles): The PXDOPs as Versatile yet Underutilized Electro-active and Conducting Polymersâ
2Beaujuge, P.M.; Reynolds, J.R. Chem. Reviews, Special Edition â" Organic Electronics 2010, 110, 268-320. âColor Control in Î -Conjugated Organic Polymers for Use in Electrochromic Devicesâ
3Beaujuge, P.; Ellinger, S.; Reynolds, J.R. Nature Materials, 2008, 7, 795-799. âThe Donor-Acceptor Approach Allows a Black to Transmissive Switching Polymer Electrochromeâ
4Beaujuge, P.M.; Amb, C.M.; Reynolds, J.R. Acc. Chem. Res., ASAP August 20, 2010 DOI: 10.1021/ar100043u âSpectral Engineering in Î -Conjugated Polymers with Intramolecular Donor-Acceptor Interactionsâ
5Steckler, T.T., Zhang, X., Hwang, J., Honeyager, R., Ohira, S., Zhang, X-H., Grant, A., Ellinger, S., Odom, S.A., Seat, D., Tanner, D.B., Rinzler, A.G., Barlow, S., Bredas, J-L., Kippelen, B., Marder, S.R., Reynolds, J.R. J. Am. Chem. Soc. 2009,131, 2824-2826. âA Spray Processable, Low Bandgap, and Ambipolar Donor-Acceptor Conjugated Polymerâ
For more information contact Prof. Seth Marder (404-385-5-6048).