The work done at IEMN was partly supported by IRCICA. The Ministère de la Recherche is acknowledged for the Ph.D. grant for T. K. Tran. Supporting Information is available online from Wiley InterScience or from the author.
Electropolymerized Self-Assembled Monolayers of a 3,4-Ethylenedioxythiophene-Thiophene Hybrid System†
Article first published online: 28 JUL 2008
Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Advanced Functional Materials
Volume 18, Issue 15, pages 2163–2171, August 11, 2008
How to Cite
Oçafrain, M., Tran, T. K., Blanchard, P., Lenfant, S., Godey, S., Vuillaume, D. and Roncali, J. (2008), Electropolymerized Self-Assembled Monolayers of a 3,4-Ethylenedioxythiophene-Thiophene Hybrid System. Adv. Funct. Mater., 18: 2163–2171. doi: 10.1002/adfm.200800304
- Issue published online: 6 AUG 2008
- Article first published online: 28 JUL 2008
- Manuscript Revised: 26 MAR 2008
- Manuscript Received: 1 MAR 2008
- conjugated systems;
- molecular junction;
- self-assembled monolayers
Self-assembled monolayers (SAMs) of a conjugated bithiophenic system connected to an alkanethiol chain have been deposited on gold surface. The electroactive bithiophenic system involves a 3,4-ethylenedioxythiophene (EDOT) unit and a thiophene ring on which an alkanethiol is attached at the internal β-position via a sulfide linkage. The analysis of the structure of the SAMs by IR spectroscopy, ellipsometry, contact angle measurement and X-ray photoelectron spectroscopy (XPS) provides consistent results indicating compact monolayers in which the alkyl linkers are arranged in an almost vertical fashion while the bithiophenic-conjugated systems are essentially parallel to the surface. Cyclic voltammetry shows that application of a few potential scans to SAMs immersed in a medium containing only a supporting electrolyte leads to the typical electropolymerization curves while the CV of the electrooxized monolayer exhibits a reversible cyclic voltammogram characteristic of a stable electroactive extended conjugated system. The characterization of the electropolymerized monolayers by IR spectroscopy, ellipsometry, contact angle measurement, and XPS indicates compact monolayers. The analysis of the current voltage characteristics of the monolayers by conducting AFM before and after electrooxidation shows that the enhancement of the effective conjugation resulting from electropolymerization leads to a significant increase of the transport properties.