Polythiophene, electrochemical properties

The development of polythiophenes since the early 1980s has been extensive. Processible conducting polymers are available and monomer derivathation has extended the range of electronic and electrochemical properties associated with such materials. Problem areas include the need for improved conductivity by monomer manipulation, involving more extensive research using stmcture—activity relationships, and improved synthetic methods for monomers and polymers alike, which are needed to bring the attractive properties of polythiophenes to fmition on the commercial scale. 

Here we introduce a personal point of view about the interactions between conducting polymers and electrochemistry their synthesis, electrochemical properties, and electrochemical applications. Conducting polymers are new materials that were developed in the late 1970s as intrinsically electronic conductors at the molecular level. Ideal monodimensional chains of poly acetylene, polypyrrole, polythiophene, etc. can be seen in Fig. 1. One of the most fascinating aspects of these polymeric... 

Synthesis and Electrochemical Properties of a Polythiophene—Viologen Polymer... 

In this article we report the synthesis and electrochemical properties of the polymer derived from oxidation of X, poly(I), and the characteristics of a microelectrochemical transistor based on the polymer. Poly(I), which is formed by electrochemical oxidation of X, Equation 1, consists of a conducting polymer backbone, polythiophene. 

Electrochemical oxidation of X produces a polymer film with polythiophene as the backbone and viologen centers as pendant redox groups. The electrochemical properties of the polymer are the combination of polythiophene and viologen. Using viologen subunits as the internal standard (one per repeat unit of the polymer), the "doping level" of the oxidized polythiophene backbone at its maximum conductivity can be measured and is about 25%. The charge transport via the pendant V2+/+ of poly(l) has been studied by... 

J.L. Bredas, R. Silbey, D.S. Boudreaux, and R.R. Chance, Chain-length dependence of electronic and electrochemical properties of conjugated systems polyacetylene, polyphenylene, polythiophene, and polypyrrole, J. Am. Chem. Soc., 105 6555-6559, 1983. 

Table 1. Structures and electrochemical properties of polypyrroles and polythiophenes...

The electrochemical properties of conductive polymer systems are important with regard to understanding the electrochemical doping process and in applications of conductive polymers as battery electrodes. We have developed a computational method, based on the Valence Effective Hamiltonian technique, which is remarkably effective in the computation of oxidation and reduction potentials of a variety of conjugated polymers (polyacetylene, polyphenylene, polythiophene, polypyrrole) and their oligomers. 

Bondarev SL, Bachilo SM, Dvornikov SS and Tikhomorov SA (1989) 2 - So fluorescence and transient S Sq absorption ofo//-tm s-/3-carotenein solid and liquid solutions. Photochem Photobiol, A Chemistry 46 315-322 Bouwman W, Jones A, Phillips D, Thibodeau P, Friel C and Christensen R (1990) Fluorescence of gaseous tetraenes and pentaenes. J Phys Chem 94 7429-7434 Bredas JL, Sdbey R, Boudreaux DS and Chance RR (1983) Chain-length dependence of electronic and electrochemical properties of conjugated systems Polyacetylene, polyphenylene, polythiophene, and poly pyrrole. J Am Chem Soc 105 6555-6559... 

G. Tourillon and F.Garnier, Structural effect on the electrochemical properties of polythiophene and derivatives, y. Electroanal. Chem., 161 51 (1984). 

Perrin, L., Legros, M., Mercier, R.G., 2015. Design of a series of polythiophenes containing C60 groups synthesis and optical and electrochemical properties. Macromolecules 48,323-336. 

F. Wu, J. Chen, R. Chen, S. Wu, L. Li, S. Chen, T. Zhao, Sulfur/Polythiophene with a Core/Shell Structure Synthesis and Electrochemical Properties of the Cathode for Rechargeable Lithium Batteries. J. Phys. Chem. C 2011,115, 6057-6063. 

The most elegant approach to design polypyrrole, polyaniline or polythiophene-based porphyrin, phthalocyanine or Schiff base matrices involves the electrochemical polymerization of suitably designed substituted N4-macrocyclic monomers. We and others have shown that the electro-oxidative polymerization of such species (see significant examples in Figure 8.3) leads to the formation of films having the electrochemical properties of the monomeric complex" . ... 

This chapter focuses on the use of polythiophene derivatives [11] as active electrode materials in electrochemical capacitors. First, the concept of electrochemical capacitors is presented in order to highlight the electrochemical properties of polythiophenes that make them suitable for this application. Second, the various wide- and narrow-bandgap derivatives of polythiophenes that have been investigated are discussed. 

Polythiophenes are generally electrogenerated in the presence of small innocent anions derived from strong acids (e.g., perchlorate, tetrafluoroborate, and hexafluophosphate) associated with lithium or tetraalkylammonium cations. The nature of the anion strongly affects the morphology and the electrochemical properties of the polymer. 

Polythiophene has been considered as an electrode in energy storage cells. Like polyaniline and polypyrrole, it offers the convenience that films with good electrochemical properties can be readily acquired using a relatively straightforward preparation procedure The films were prepared on a platinum electrode using 1 M... 

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