Conducting Polypyrrole doped with Phthalocyaninesulfonates - new materials for chemical sensors
- Polypyrrole - a conducting polymer - is used as an active electrode of a quartz micro ballance and considered as a gate electrode in all-polymer field effect transistors used as chemical sensor. We use substituted phthalocyanines as dopants of polypyrrole as they offer the possibility to enhance the dopant concentration as well as to include functionalized groups. We studied these films by photoelectron spectroscopy, NEXAFS, PEEM, and TEM. These investigations revealed that the electronic structure as well as the morphology are highly dependent on the dopant’s structure. We suggest a new charge transport model for 5-ring heterocycle conductive polymers. Whereas in the standard model only the carbon backbone is considered for the charge transport, we found by NEXAFS investigations that the heteroatom has a considerable high participation in the gap states, which are responsible for the charge transport. The dopants π-interactions force the nitrogen lone pair wave functions to contribute to the conducting polymer π-system. This is aPolypyrrole - a conducting polymer - is used as an active electrode of a quartz micro ballance and considered as a gate electrode in all-polymer field effect transistors used as chemical sensor. We use substituted phthalocyanines as dopants of polypyrrole as they offer the possibility to enhance the dopant concentration as well as to include functionalized groups. We studied these films by photoelectron spectroscopy, NEXAFS, PEEM, and TEM. These investigations revealed that the electronic structure as well as the morphology are highly dependent on the dopant’s structure. We suggest a new charge transport model for 5-ring heterocycle conductive polymers. Whereas in the standard model only the carbon backbone is considered for the charge transport, we found by NEXAFS investigations that the heteroatom has a considerable high participation in the gap states, which are responsible for the charge transport. The dopants π-interactions force the nitrogen lone pair wave functions to contribute to the conducting polymer π-system. This is a novel approach concerning the application as chemical sensors since the reversible interaction of the analyte modifies the dopant and not the matrix.…
Author: | Ricardo Pablo Mikalo, Günter Appel, Patrick Hoffmann, Dieter SchmeißerORCiD |
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URL: | http://www.dpg-verhandlungen.de/year/2000/conference/regensburg/part/o/session/15/contribution/1?lang=en |
Title of the source (German): | Verhandlungen der Deutschen Physikalischen Gesellschaft |
Publisher: | Deutsche Physikalische Gesellschaft |
Place of publication: | Bad Honnef |
Document Type: | Conference Proceeding |
Language: | English |
Year of publication: | 2000 |
Tag: | X-Ray absorption spectroscopy (XAS); X-ray photoelectron spectroscopy (XPS); conducting polymer; gas sensor; photo emission electron spectroscopy (PEEM); polypyrrole; quartz crystal micro ballance (QMB); transmission electron microscopy (TEM) |
Series ; volume number: | Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Band 35 |
Faculty/Chair: | Fakultät 1 MINT - Mathematik, Informatik, Physik, Elektro- und Informationstechnik / FG Angewandte Physik und Halbleiterspektroskopie |