Conducting polymers, in electrochemical

Applications of Electronically Conducting Polymers in Electrochemical Science... 

The advantages for the use of intrinsically conducting polymers in electrochemical capacitors rather than carbon-based or mixed metal oxide electrodes may be summarised as follows ... 

A. A. Pud, Stability and degradation of conducting polymers in electrochemical systems. Synth. Met. 66 ... 

Robert Nowak (4), associated with A. G. MacDiarmid and Allen Heeger, was the first in 1977 to use an electronically conducting polymer in electrochemical studies. Thus, the substance used was the... 

LIKELY FUTURE APPLICATIONS OF ELECTRONICALLY CONDUCTING POLYMERS IN ELECTROCHEMICAL SCIENCE... 

There are also a number of other variables to consider when planning the electrochemical synthesis of conducting polymers in ionic liquids. While most of these variables also exist for the synthesis of the polymers in molecular/solvent systems and have been investigated in detail, it is worth considering that the influence of any of these factors may be different when utilizing ionic liquids as the growth medium because of their distinctly different properties. These are discussed in more detail below. 

Fig. 7.4 The cations and anions utilized to date for the electrochemical synthesis of conducting polymers in ionic liquids, and their abbreviations.

Recent application of conducting polymers for electrochemical capacitors has been reviewed. The ionically conducting polymers have the potential to replace wet-type capacitors by dry-type ones. Especially important are the gel electrolyte systems whose ionic conductivity is high, and thus high capacitance can be obtained with them in EDLC. We believe that the combination of high surface area... 

Recent applications of SPM techniques have revealed new details of the electrical properties of conducting polymers. In one example, STM images were taken of the granular structure of electrochemically prepared polyaniline films. Simultane-... 

In contrast to mediators, also redox polymers can be used. These polymers are mainly characterized by the presence of specific electrochemically active sites. There are different possibilities to facilitate redox transfer by shuttling electrons via redoxactive groups in non-conductive or conductive polymers. In general, a redox polymer consists of a system where a redoxactive molecule is covalently bound to a polymer backbone which may or may not be electroactive. Erequently, electroactive polymers are formed by the electropolymerization of suitable monomer complexes. A few representative examples of electron shuttle molecules are shown in Eig. 1. 

Poly thiophene, PTP, and polypyrrole, PPR, blends with PS and PC were prepared by Wang et al. [1990] by thiophene or pyrrole electrochemical polymerization using electrodes coated with PS or PC hlms. The thiophene or pyrrole diffuses into the fihn and polymerizes in-situ in the film. Threshold conductivity occurs at 18 wt% for both conducting polymers in PS. Lower levels exist for PTP (12 wt%) and PPR (7 wt%) in PC. Miscibility of PPR/PC is attributed to the lower threshold limit as phase separated blends would be expected to have higher values. Previous studies with polyacetylene/PS blends reported threshold conductivity at 16 wt% polyacetylene [Aldissi and Bishop, 1985]. 

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