Conductive polymer electrodes

Table 3. Battery Characteristics for Conductive Polymer Electrodes...

The first tme commercialization of a conductive polymer electrode in a battery ceU has been carried out by Bridgestone/Sienko who market a... 

A conductive polymer electrode has been designed specifically for the cathodic protection of steel reinforcing bars in concrete and is marketed under the trade name Ferex . The anode consists of a 16 AWG stranded copper conductor surrounded by a carbon-loaded polymeric coating similar to that used on the Anodeflex system ) to provide a nominal anode diameter of 8 mm The manufacturer claims that at the maximum recommended current density of 0 08 Am the anode life in concrete will be 32 years with a proportionately longer life at lower current densities. 

In the case of Ni(OH)2 and conductive polymer electrodes, solvent and anions intercalate into the electrode at anodic potentials. Electrochemical quartz crystal microbalance (EQCM) is a useful technique for monitoring the ingress and egress of solvent and anions in these materials. 

Coutanceau C, El Hourch A, Crouigneau P, Leger JM, Lamy C. 1995. Conducting polymer electrodes modified by metal tetrasulfonated phthalocyanines Preparation and electro-catalytic behaviour towards dioxygen reduction in acid medium. Electrochim Acta 40 2739-2748. 

Organic salt and conducting polymer electrodes The surface of an organic electrode may provide enzymes with smooth electron transfer. 

An electrochemical capacitor is a device that stores electrical energy in the electrical double layer that forms at the interface between an electrolytic solution and an electronic conductor. The term applies to charged carbon—carbon systems as well as carbon-battery electrode and conducting polymer electrode combinations sometimes called ultracapacitors, supercapacitors, or hybrid capacitors. 

Chen Liu Y, Minett AI, Lynam C, Wang J, Wallace GG. Flexible, aligned carbon nanotube/conducting polymer electrodes for a lithium-ion battery. Chem Mater 2007 19 3593-3597. 

In this section, we review recent developments of redox capacitors with conducting polymer electrodes and EDLC with SPE or gel electrolyte systems. 

B. Supercapacitor Based on Electronically Conducting Polymer Electrode... 

Feb. 28,1934, Camden, NJ, USA - Mar. 3,2003, Cincinnati, OH, USA) Mark received a B.A. in chemistry from the University of Virginia and a Ph.D. from Duke University. He was postdoc at the University of North Carolina and at the California Institute of Technology. After a faculty position at the University of Michigan he served from 1970 until his death as Professor in the Chemistry Department of the University of Cincinnati. Mark was electrochemist and analytical chemist. His major contributions concern spectroelectrochemistry and conducting polymer electrodes. He was among the pioneers of kinetic methods of analysis. His scientific work is documented in over 300 publications and 14 books which he either has written or edited. 

Modified electrodes for this analytical purpose have mostly been formed by electrode adsorption of the mediator systems on the electrode surface or by electropolymerization [24,116]. Recently, for example, NAD(P)H oxidations have been performed on platinum or gold electrodes modified with a monolayer of pyrroloquinoline quinone (PQQ) [117] or on poly(methylene blue)-modified electrodes with different dehydrogenases entrapped in a Nafion film for the amperometric detection of glucose, lactate, malate, or ethanol [118]. In another approach, carbon paste electrodes doped with methylene green or meldola blue together with diaphorase were used for the NADH oxidation [119]. A poly(3-methylthio-phene) conducting polymer electrode was efficient for the oxidation of NADH [120]. By electropolymerization of poly(aniline) in the presence of poly(vinylsulfonate) counterions. 

The direct electrochemistry of redox proteins has developed significantly in the past few years. Conditions now exist that permit the electrochemistry of all the proteins to be expressed at a range of electrodes, and important information about thermodynamic and kinetic properties of these proteins can be obtained. More recently, direct electron transfer between redox enzymes and electrodes has been achieved due to the more careful control of electrode surfaces. The need for biocompatible surfaces in bioelectrochemistry has stimulated the development of electrode surface engineering techniques, and protein electrochemistry has been reported at conducting polymer electrodes 82) and in membranes 83, 84). Furthermore, combination of direct protein electrochemistry with spectroscopic methods may offer 85) a novel way of investigating structure-function relationships in electron transport proteins. 

Galal, A. Electrocatalytic oxidation of some biologically important compounds at conducting polymer electrodes modified by metal complexes. J. Solid State Electrochem. 1998, 2, 7-15... 

Supercapacitors containing electronically conducting polymer electrodes are of great interest, in particular for hybrid and electric vehicles due to their potential in the storage of large amounts of energy in a small volume. The largest hurdles towards marketable products are material development, production scale up and quality control. 

Fletcher S 1993 Contribution to the theory of conducting-polymer electrode in electrolyte solutions J. Chem. Soc. Faraday Trans. 89 311-20 Kanatzidis M G 1990 Conductive Polymers Chem. Eng. News 68(49) 36-54 Bard A J and Faulkner L R 1980 Electrochemical Methods Fundamentals and Applications (New York Wiley)... 

Halik and coworkers subsequently extended this process to pattern conducting polymer electrodes, such as poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonic acid (PEDOT-PSS) [11]. In this process, PEDOT-PSS is uniformly coated on a substrate that has prepattemed photoresist. The PEDOT-PSS-coated substrate is then immersed in acetone to swell the photoresist underneath the... 

The barrier is to be constructed of three layers of pol miers consisting of a protonconducting electrolyte (electronic insulator) sandwiched between electronically conductive polymer electrodes. Candidate pol5mier compositions will be selected based upon existing knowledge. If this knowledge is not sufficient, new or modified compositions will be developed. Appropriate catalyst materials will be added at the electrolyte/electrode interfaces. 

The modification of the monomer by chemical bonding (i.e. covalent grafting) has been also shown to be very efficient for obtaining modified conducting polymer electrodes,... 

Besides methanol and ethanol, only a few other small molecules (HCOOH, HCHO, CO), have been oxidized at electron conducting polymer electrodes modified by incorporation of platinum microparticles. The first study on formic acid oxidation at Pt particles dispersed in a PAni matrix was carried out, as early as 1986, by Gholamian et al. [57], They found that the incorporation of 100 pg cm of Pt into PAni was sufficient to enhance considerably the oxidation rate of formic acid (ten-fold increase). The cyclic voltammograms recorded with 0.5 M HCOOH in 0,5 M H2SO4 displayed an enhanced oxidation current particularly for the first oxidation peak at 0.2 V/SCE, attributed to the oxidation of the weakly adsorbed intermediate (reactive species). The second peak, at 0.6 V/SCE, attributed to the oxidation of the strongly chemisorbed... 

The electrocatalytic oxidation of alcohols is possible by using modified conductive polymer electrodes. One of the most interesting examples of such a reaction is the electro-oxidation of methanol with highly dispersed platinum-based particles inserted in a polymeric matrix. 

The immobilization of an active species into a conducting polymer layer allows one to obtain active electrodes for the reduction of various organic halides. Polypyrrole containing viologen electrodes appear to be active for the reduction of alkyl dibromide [177] or hexachloroacetone [178], Cobalt-bipyridyl-polypyrrole films are active electrodes for the reduction of alkyl chloride [107], The mechanism of this reaction is similar to that observed in the homogeneous phase. This confinns one of the major interests of the modified conductive polymer electrodes, i,e. the possibility of performing catalytic reactions with smaller amounts of active catalyst in comparison to homogeneous catalysis, and then to avoid problems related to the separation of products from the solution which contains this catalyst. 

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