Poly electrochemical behavior

In this paper we describe the preparation of thin polymer films by surface catalysis and anodic deposition. The results indicate that both synthesis routes produce orientationally ordered films that have similar infrared spectra. It is also shown that thin ordered films of poly(thiophene) have different electrochemical behavior than the fibrous films that are electrically conducting. 

Preparation and Electrochemical Behavior of Microelectrodes Modified with Poly(I). A microelectrode array consisting of eight Pt microelectrodes is cleaned and platinized as described in the Experimental Section. Poly(I) is deposited on the platinized microelectrode array by scanning the potential of the electrode(s) from 0 V to 1.5 V vs. Ag+/Ag in a solution of 0.2 MX in CH3CN/O.I M [U-BU4N]PFg. The resulting array is illustrated in Scheme I. The... 

This section is organized as follows we first start with a discussion of the electrochemical behavior of the Roussin-type synthetic iron- sulfur clusters for their historic importance and as an interesting introduction to poly iron-sulfur centers redox chemistry. Then we review iron-sulfur centers in proteins and artificial models in the order of increasing iron content. Finally, biological iron-sulfur centers and artificial models directly linked to other inorganic centers, the so-called bridged molecular assemblies, are considered. 

The electrochemical behavior of poly(ferrocenylsilanes) has been studied at three levels—in solution by cyclic voltammetry, as films deposited on electrodes, and in the solid state via iodine doping. Solution cyclic voltammetric oxidation and reduction has shown that the polymer, where R/R is Me/Me, reversibly oxidizes in methylene chloride in two stages, apparently with the first oxidation being on alternating iron atoms along the chain.29 Films cast on electrodes behave in a similar way and also show an electrochromic response to oxidation and reduction.30... 

The electrochemical behavior of poly(pyrrole) films prepared and cycled in an AICI3 [C2mim][Cl] melt was investigated in detail and improvements in reproducibility and the rate of oxidation and reduction of these films were observed compared to films prepared under similar conditions in acetonitrile [49]. This was postulated to be a result of an increase in the porosity of poly(pyrrole) films deposited from the melt compared to those from acetonitrile, although attempts to describe this porosity using porous electrode models were not totally conclusive. 

The difference in oxidation potentials (A ) detected for the two waves found for the poly(ferrocenylsilanes) 15 (R = R = Me, Et, -Bu, -Hex), which provides an indication of the degree of interaction between the iron sites, varies from 0.21 V (for 15 (R = R = Me)) to 0.29 V (for 15 (R = R = -Bu or -Hex)) (63). This indicates that the extent of the interaction between the ferrocenyl units in poly(ferrocenylsilanes) depends significantly on the nature of the substituents at silicon, which may be a result of electronic or conformational effects (63). Unsymmetrically substituted poly(ferrocenylsilanes) show similar electrochemical behavior (59). In addition, polymer 15 (R = Me, R = Fc) shows a complex cyclic voltammogram which indicates that interactions exist between the iron centers in the polymer backbone and the ferrocenyl side groups (59). 

The electrochemical behavior of poly(RCOT)s has also been examined [40]. As expected from the electrochemical properties of unsubstituted polyacetylene, films of poly(RCOT)s coated on an electrode and immersed in an acetonitrile electrolyte solution (in which the polymers are not soluble) are found to undergo reversible oxidative and reductive doping. Unlike unsubstituted polyacetylene, these films may be prepared readily by casting from solution, or, in the case of poly(scc-butylCOT), by electrodecomposition from a THF solution. In contrast to the voltammetry of polymer films, cyclic voltammograms of methylene chloride... 

Thinh, P., Basavaraja, C., Kim, D.G., Huh, D. Characterization and electrochemical behaviors of honeycomb-patterned poly(N-vinylcarbazole)/polystyrene composite films. Polym. Bull. 69(1), 81-94 (2012)... 

In Chapter 8, coauthored by Kelly and Vos, the electrochemical behavior of osmium and ruthenium poly(pyridyl) redox polymers is discussed in some detail. Vos has made significant contributions in this area. This chapter ties in well with the more general discussion presented by Lyons in Chapters 1 and 2, in that many of theoretical concepts addressed in the latter chapters are again discussed by Kelly and Vos with specific reference to redox-active metallopolymer materials. 

GAMMA IRRADIATION OF POLY(PYRROLE)-COATED Pt ELECTRODES THE EFFECT ON THE ELECTROCHEMICAL BEHAVIOR... 

Ates M, Yilmaz K, Shahryari A, Omanovic S, Sarac AS. A study of the electrochemical behavior of poly [n-vinyl carbazole] formed on carbon-fiber microelectrodes and its response to dopamine. IEEE Sens J 2008 8(10) 1628-39. 

Kitani, A., et al. 1999. Electrochemical behaviors of polyaniline/poly(aniline-2,5-disulfonic add)... 

A. Kitani, K. Satoguchi, K. Iwai, S. Ito, Electrochemical behaviors of poly-aniline/polyaniline-sulfonic acid composites, Synthetic Metals 1999, 102, 1171. 

The electrochemical behavior of cast films of poly(3-(3 -thienyl)-propanesulfonic acid) in acetonitrile/HBF4 containing 6 % water is... 

Figure 4.18 Electrochemical behavior of a cast film of poly(3-(3 -thienyl)propane sulfonic acid) at several scan rates in acidic electrolyte solution, 0.5 M HBF4 (6% HiOj-acetonitrile where the working electrode was a 3100 A thick film of poly(3-(3 -thienyl)propanesulfonic acid) (M = H) cast on ITO (indium tin oxide), the counter electrode was a Pt mesh and the reference electrode was Ag/Ag. Cyclic voltammograms were obtained at (a) 200, (b) 100 and (c) 50mV/s respectively. (Reprinted from Synthetic Metals, 40, Y. Ikenoue, H. Tomozawa, Y. Saida, M. Kira, H. Yashima, 333. Copyright (1991), with permission from Elsevier.)...

T. Yamamoto, Y. Honda, T. Sata and H. Kokubo. Electrochemical behavior of poly(3-hexylthiophene). Controlling factors of electric current in electrochemical oxidation of poly(3-hexylthiophene)s in a solution. Polymer 45(6), 1735-1738 (2004). 

The presence of at least one alkyl group on the cyclopentadienyl motif is required to induce solubility in these poly(ferrocenylene persulfide)s. These polymers show two reversible oxidations. This type of electrochemical behavior is fairly common in ferrocene polymers where the ferrocene units are separated by short spacers as will be pointed out in the next section. 

Poly(ferrocenylsilane)s have been investigated extensively in terms of their electrochemical behavior. The general observation of these investigations is that under cyclic voltammetric conditions these polymers show two reversible oxidation (Fe(II)/Fe(III)) peaks separated by a AE1/2 that varies from about 0.16 to 0.29 V. The observation of two oxidation peaks has been explained as two successive events where the first oxidation involves a set of alternate ferrocene units followed by the second oxidation of the other alternate set. The second oxidation occurs at a higher potential than the first one [3,7]. 

Most poly pyrrole films have been prepared using inert electrodes, such as Pt [27], Au [28], or glassy carbon [29]. The main problem associated with the electrogeneration of polypyrrole onto active metals, such as Ti, Fe, stainless steel, or Al, is related to the interference of the electrochemical behavior of the metal with the... 

Pyrrole has been functionalized with both reducible and oxidizable substituents. Examples of the first group are compounds 51-53, which have been homo- and copolymerized [254,255] poly(51) has been demonstrated to catalyze oxygen reduction. Attempts to polymerize 54 did not lead to a clean reaction [256]. Substantial amounts of dark-colored soluble products were formed. The benzoquinone 55 was successively polymerized [256] and the electrochemical behavior of the relevant polymer was studied. 

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