Showing papers on "Cyclic voltammetry published in 1980"
TL;DR: In this paper, the theory of homogeneous redox catalysis in the context of cyclic voltammetry is presented for the EC reaction scheme, i.e., the simplest of the mechanisms in which the initial electron-transfer process is followed by chemical reaction.
309 citations
TL;DR: In this paper, a model for the cyclic voltammetric behavior of polymeric films on electrode surfaces was proposed, which incorporates non-equivalent redox sites with interconversion between such sites, electron-transfer kinetics at substrate/film interface and diffusion within the film.
279 citations
TL;DR: In this article, the oxidation of substituted catechols was studied by cyclic voltammetry, chronoamperometry, rotating ring-disk electrode, and coulometry.
Abstract: The oxidation of substituted catechols was studied by cyclic voltammetry, chronoamperometry, rotating ring-disk electrode, and coulometry. The results showed that the quinones that were formed from the oxidation of substituted catechols reacted with the basic forms of the starting material to yield the dimeric product. These products were generally unstable and rapidly polymerized or underwent some other irreversible reaction to form an electroinactive product. For 3,4-dihydroxyacetophenone and propriophenone, the intermediate was stable long enough to be observed in cyclic voltammetry. The rate of the coupling reaction was found to correlate well with the Hammett P-q parameters and indicated that there was substantial negative charge in the transition state. Finally, an analysis of the coulometric n-values along with the iat1/2/C values indicated that the initial coupling product was a diphenyl ether. Analysis of the coulometry products showed extensive polymerization.
184 citations
TL;DR: In this paper, the electrochemical oxidation of sulfur amino acids has been investigated by ac measurements and cyclic voltammetry at solid electrodes (Au, vitreous carbon), and a reaction path is proposed.
135 citations
132 citations
TL;DR: In this article, the electrochemical properties of FAD adsorbed on graphite were studied with cyclic voltammetry and a film with a surface coverage of up to 2×10−8 mol cm−2 was formed after 4 h.
132 citations
TL;DR: In this paper, the early stages of Pb condensation on Ag(111) have been studied in ultrahigh vacuum and in an electrochemical cell, and a particular case of Stranski-Krastanov type is found for the subsequent growth.
99 citations
TL;DR: The use of radio frequency plasma discharges of neat vinylferrocene to chemically modify pyrolytic graphite electrode surfaces is discussed in this paper, where the results indicate that the surface composition varies as a function of placement of the substrate in the plasma reactor.
81 citations
TL;DR: In this paper, the reduction of tert-nitrobutane in acetonitrile has been studied by cyclic voltammetry by the fit of data to theoretical voltammograms obtained from digital simulations.
78 citations
TL;DR: In this article, it was shown that crossing of anodic and cathodic traces is frequently observed on cyclic voltammograms featuring the electrochemical induction of a chemical reaction in the case where the product standard potential is positive to the reactant reduction potential.
65 citations
TL;DR: In this paper, the electrochemical oxidation of three proteins: RNAase A, bovine serum albumin (BSA), and Concanavalin A, has been investigated on solid electrodes (gold, platinum, vitreous carbon, carbon paste electrode) using a.c. voltammetry and cyclic voltammetric.
TL;DR: In this article, the polarization characteristics of acid zinc sulphate electrolytes containing various amounts of germanium and cobalt were examined by cyclic voltammetry and the effects of zinc and acid concentration, temperature, and surface preparation were also investigated.
Abstract: The polarization characteristics of acid zinc sulphate electrolytes containing various amounts of germanium and cobalt were examined by cyclic voltammetry. The effects of zinc and acid concentration, temperature, and surface preparation were also investigated. Small concentrations of impurities are shown to cause measurable changes in polarization behaviour. Levels as low as 0.02 mgl−1 Ge and 0.1 mgl−1 Co can be detected using this technique. The actual mechanism of impurity behaviour is more clearly delineated using this technique and evaluation of the data from these tests indicate that germanium and cobalt form local galvanic cells. The results of these short-term tests are shown to correlate with classical long-term efficiency tests. The deposit morphologies obtained for short-time cathodic cycles were also studied using scanning electron microscopy.
TL;DR: In this article, the presence of unusually reactive, firmly bonded ruthenium oxide species on the surface of thermally prepared RuO2 and RuO 2 /TiO 2 coatings on titanium was demonstrated by cyclic voltammetry techniques.
TL;DR: In this paper, the transfer of the picrate ion across the interface between two immiscible electrolyte solutions, 0.05 M LiCl in water and 0.5 M tetrabutylammonium tetraphenylborate in nitrobenzene, was investigated by electrolysis with the electrolyte dropping electrode and by cyclic voltammetry.
TL;DR: In this article, the reduction of molecular oxygen was investigated on single crystal rutile electrodes and cyclic voltammetry and a rotating ring-disk electrode were employed to elucidate the mechanism and energetics of the reaction.
01 Jun 1980
TL;DR: In this article, the surface reactivity of FeS 2 has been investigated in terms of the S 2 2−, disulfide, structure in the latter mineral and cyclic voltammetry reveals two, almost reversible, monolayer surface processes in the potential range −0.2 to + 0.45 V at pH 1.
Abstract: Electrochemical studies on the surface reactivity of FeS 2 are described. Comparisons with FeS were made in order to examine if the behavior observed with FeS 2 is characteristic of the S 2 2− , disulfide, structure in the latter mineral. Cyclic voltammetry reveals two, almost reversible, monolayer surface processes at FeS 2 in the potential range −0.2 to +0.45 V at pH 1. FeS behaves much less reversibly and with three or four distinguishable electrochemical surface processes occurring over a potential range somewhat different from that for FeS 2 . At more alkaline pHs, the surface reactivity of FeS 2 is less reversible and involves a thicker surface region, some 20 times that in acid (pH 1) solutions. In distinction to the behavior found with PbS, reported previously, reoxidizable solution-soluble species (S 2− or SH − ) are not generated in the potential cycling at FeS 2 or FeS. SEM photography gives some idea of the surface morphological changes that occur on repetitive cycling, and the associated changes in the Fe:S ratio in the surface region are revealed by X-ray emission experiments.
TL;DR: In this article, Mechanisms of oxidation reactions are proposed to explain the formation of these products, and materials formed in anode-limited cells during forced overdischarge include,,,,,, and a substance with infrared absorption at 1070 cm−1.
Abstract: Cyclic voltammetry and constant current electrolysis studies of solutions showed that , , , , and are produced as oxidation products. Mechanisms of oxidation reactions are proposed to explain the formation of these products. Forced overdischarge of cathode limited cells produces which reacts with present in the cell to form . Materials formed in anode limited cells during forced overdischarge include , , , , , and a substance with infrared absorption at 1070 cm−1. "Charging" of cells involves regenerative processes so that only small amounts of products accumulate in the cell.
TL;DR: In this article, the electrochemical behavior of 25 pyrylium perchlorates and 2 benzopyryllium per chlorates in acetonitrile was investigated using voltammetry and oscillopolarography at a rotating disc electrode.
TL;DR: In this paper, it was shown that up to twenty monolayers of thionine can be irreversibly coated on to platinum or tin oxide electrodes and the reduction of Fe(III) is much slower on a coated electrode compared to a clean electrode.
TL;DR: In this paper, it was shown that coordination of cobalt by surface carboxylate groups causes extraordinarily slow electron transfer for the Co(III/II) step in tetra-(aminophenyl) porphyrin.
Abstract: : Electrochemistry of tetra-(aminophenyl) porphyrin covalently attached to glassy carbon and then cobalt-metalled, was investigated in DMSO and CH CN solvents in the pressence of pyridine. Shifts in formal potential were used to measure complex stability constants and coordination number for the pyridine complexes of the immobilized metalloporphyrin. Unusually slow electrochemistry of the Co(III/II) reaction was also studied cyclic voltammetry and by reflectance spectroelectrochemistry. It is proposed that coordination of cobalt by surface carboxylate groups causes extraordinarily slow electron transfer for the Co(III/II) step. (Author)
TL;DR: In this paper, cyclic voltammetry experiments on high spin manganese materials reveal a quasireversible Mn(III)/Mn(II) redox and a pronounced salicylaldehyde substituent effect on cathodic peak potential.
TL;DR: In this paper, the electrochemical reduction of triorganohalo-silanes and -germanes in 1,2-dimethoxyethane has been investigated by polarography, cyclic voltammetry, controlled potential coulometry, and macroscale electrolysis.
TL;DR: In this paper, the electrochemistry of polycrystalline silver in 1 mol kg−1 KOH at temperatures between 295 K and 478 K has been studied using cyclic voltammetry and cyclical galvanostatic charging.
TL;DR: In this paper, the half-wave d.c. oxidation potentials of the substrates of alkaline phosphatase: dihydrogen o-hydroxyphenyl phosphate (I) and diHydrogen p-aminophenyl phosphate(II) on platinum electrodes are equal to 681, 516 and 696 mV vs. N.H.E. at pH S.o (I,II) and pH 4.7 (III) respectively.
TL;DR: In this paper, the electrochemical properties of three dipyridinium salts were studied in order to assess their behavior for use as mediators in titrations of biological molecules, and they were used in indirect coulometric titration of large biological redox molecules if there is sufficient separation between the formal potential, E 1 0′, of the mediator and the E 0′ of the biological molecules.
TL;DR: In this article, the electrochemical reduction of organic solvents with supporting electrolytes was investigated using cyclic voltammetry, coulometry, and UV-VIS spectroscopy.
Abstract: The electrochemical reduction of has been investigated in organic solvents with supporting electrolytes, using cyclic voltammetry, coulometry, and UV‐VIS spectroscopy An overall 20F reduction was observed Comparison of voltammograms of , S, and with those of reduced solutions demonstrated that intermediate species are formed in the reduction of These intermediates decompose slowly to form S and Reaction mechanisms consistent with these findings are discussed
TL;DR: In this article, the reduction of dicyanocob(III)alamin was investigated using potential-dependent potentiostatic chronoamperometry, which allows a simpler analysis than cyclic voltammetry for systems involving a slow initial charge transfer step.
TL;DR: In this article, an enzyme-coenzyme complex was immobilized on the surface of a glassy carbon electrode and investigated with cyclic voltammetry in ethanol-containing buffers.
Abstract: An enzyme-coenzyme complex was immobilized on the surface of a glassy carbon electrode and investigated with cyclic voltammetry in ethanol-containing buffers. The complex consists of an Liver Alcohol Dehydrogenase molecule to which an NAD-analogue is covalently attached via its straight six-carbon, spacer. One cycle was observed but repeated recycling could not be carried out. presumably due to catalytic decomposition of the coenzyme at the electrode surface.
TL;DR: In this article, the application of convolution potential sweep voltammetry to quantitative analysis of the linear potential sweep or cyclic voltameters of the ion or electron transfer across the interface between two immiscible electrolyte solutions was discussed.