scholarly journals Current calculation of irreversible electrode reaction mechanismsin linear sweep voltammetry

2021 ◽  
Vol 9 (3) ◽  
Author(s):  
Ján Mocák ◽  
Estera Rábarová
Keyword(s):  
Chemical Reaction ◽  
Infinite Series ◽  
Digital Simulation ◽  
Linear Sweep Voltammetry ◽  
Electrode Reaction ◽  
Potential Range ◽  
Linear Sweep ◽  
Potential Region ◽  
Current Function ◽  
Simulation Techniques

Application of exponential infinite series gives highly accurate analytical solution contributing to the theory of linear sweep voltammetry for single scan experiments. We have calculated theoretical dimensionless current function (usually denoted as π1/2χ(bt)) at relevant potentials for irreversible charge transfer without a coupled chemical reaction. For this purpose several transformation techniques were used, which convert the derived infinite series into summable sequences. Since infinite series of further electrochemical mechanisms with irreversible electrode reaction have similar features (particularly those comprising preceding and catalytic chemical reaction), the same approach can be successfully applied also for further electrochemical mechanisms. The respective infinite series are divergent in the most important potential region at and after voltammetric peak therefore their transformation by Epsilon and Levin transform techniques was used. Necessary arbitrary precision arithmetic (APA) was implemented by UBASIC. The results were compared to the customary solution of Nicholson and Shain, who computed the current-potential curves by means of numerical solution of the integral equations but with a much lower precision. Our results were obtained in a broad potential range including the potential regions where the series are divergent. Obtained current functions are precise to 12 valid decimal numbers, which is utilizable for evaluation of the results achieved by various faster but less precise digital simulation techniques.

Electrochemical Studies of Some Carbazole Derivatives via Cyclic Voltammetry and Convolution – deconvolution Transforms

2011 ◽  
Vol 14 (4) ◽  
pp. 251-258 ◽  
Author(s):  
Abdullah M. Asiri ◽  
Salman A. Khan ◽  
Ibrahim S. El-Hallag ◽  
Ibrahim S. [email protected]
Keyword(s):  
Cyclic Voltammetry ◽  
Reaction Pathway ◽  
Digital Simulation ◽  
Simulation Method ◽  
Electrode Reaction ◽  
Tetraethylammonium Chloride ◽  
Cyclic Voltammetric Study ◽  
Simulation Techniques ◽  
Electrochemical Parameters ◽  
Sequential Electron

Three carbazole chromophores derivatives featuring dicyno, cyano, ethyl acetate and dimethyl acetate groups as an acceptor moiety with a ? – conjugated spacer and N-methyl dibenzo[b]pyrole as donor were investigated electrochemically at a platinum electrode in 0.1 mol/L tetraethylammonium chloride (TEACl) in acetonitrile solvent via cyclic voltammetry, convolution – deconvolution transforms and digital simulation techniques. Cyclic voltammetric study revealed that the presence of a single reversible oxidative peak due to two sequential electron transfer (EE scheme) and unidirectional reductive peak which proceed as ECEC mechanism. The electrode reaction pathway, the relevant chemical and electrochemical parameters of the investigated carbazole chromophores were determined using cyclic voltammetry, convolution- deconvolution transforms and chronoamperograms. The extracted electrochemical parameters and the nature of the electrode reaction were verified & confirmed via digital simulation method.

Study of the CEE mechanism by voltammetry and chronoamperometry

1986 ◽  
Vol 64 (12) ◽  
pp. 2319-2323 ◽  
Author(s):  
Andrzej Lasia
Keyword(s):  
Finite Difference ◽  
Kinetic Parameters ◽  
Chemical Reaction ◽  
Electrode Surface ◽  
Linear Sweep Voltammetry ◽  
Electrochemical Reactions ◽  
Linear Sweep ◽  
Bivalent Metal ◽  
Finite Difference Technique ◽  
Implicit Finite Difference

The electroreduction of bivalent metal cations may proceed by a CEE mechanism with a heterogenous chemical reaction on the electrode surface. The applications of the convolutive linear sweep voltammetry and chronoamperometry to study that mechanism are presented. The behaviour of the electrochemical reactions was simulated using an implicit finite difference technique for different values of kinetic parameters. The simulated curves were analysed and an agreement between the introduced and obtained data was found.

scholarly journals Voltammetric Studies of Anthracen-9-ylmethylene-(3,4-dimethyl-isoxazol-5-yl)-amine Compound at Platinium Electrode

2015 ◽  
Vol 18 (3) ◽  
pp. 177-181 ◽  
Author(s):  
A. A. Al-Owais ◽  
I. S. El-Hallag
Keyword(s):  
Cyclic Voltammetry ◽  
Radical Cation ◽  
Reaction Pathway ◽  
Digital Simulation ◽  
Electrode Reaction ◽  
Simulation Techniques ◽  
Electrochemical Parameters ◽  
Voltammetric Behavior ◽  
Voltammetric Studies

The voltammetric behavior of anthracen-9-ylmethylene-(3,4-dimethyl-isoxazol-5-yl)-amine compound at Platinium electrode has been performed via convolutive cyclic voltammetry and digital simulation techniques using a conventional platinium electrode in 0.1 mol L-1 tetrabutylammonium perchlorate (TBAP) in acetonitrile solvent (CH3CN). The compound loss one electron forming radical cation followed by fast chemical step and the radical cation loss another two electrons producing trication which followed by chemical reaction (ECEC). Cyclic voltammetry and convolutive voltammetry were used for determination of the chemical and the electrochemical parameters of the electrode reaction pathway of the investigated compound. The Electrochemical parameters such as α, ks, Eo , D, and kc of the investigated isoxazol derivative were verified via digital simulation technique. Voltammetric studies of the investigated isoxazol derivative compound under consideration was presented and discussed.

The anodic oxidation of carbon monoxide on gold in acid solutions

1984 ◽  
Vol 37 (12) ◽  
pp. 2415 ◽  
Author(s):  
TR Farrugia ◽  
RA Fredlein
Keyword(s):  
Carbon Monoxide ◽  
Anodic Oxidation ◽  
Linear Sweep Voltammetry ◽  
Oxidation Of Co ◽  
Oxide Formation ◽  
Linear Sweep ◽  
Potential Region ◽  
Scan Rate ◽  
Adsorption Of Co ◽  
Oxidation Of Carbon Monoxide

The anodic oxidation of carbon monoxide on gold was studied in the oxide-free potential region, linear sweep voltammetry being used to minimize electrode poisoning. Only when pco < c. 0.3 atm or when the reaction was inhibited by impurities were the plots of i against square root of scan rate linear. In other cases, i attained constant values at high scan rates; this is interpreted, together with other evidence, as due to the adsorption of CO prior to the start of the scan. Good Tafel plots were obtained under conditions where i was independent of scan rate, and the kinetic parameters are shown to be consistent with the Gilman reactant-pair mechanism. In the potential region of oxide formation on gold, the steady-state oxidation of CO proceeded with the formation of colloidal gold. The mechanism in this potential region was not investigated.

scholarly journals A study of the electrochemical behavior of methomyl on a gold electrode in a neutral electrolyte

2009 ◽  
Vol 74 (5) ◽  
pp. 573-579 ◽  
Author(s):  
Andjelka Tomasevic ◽  
Milka Avramov-Ivic ◽  
Slobodan Petrovic ◽  
Mica Jovanovic ◽  
Dusan Mijin
Keyword(s):  
Gold Electrode ◽  
Hplc Analysis ◽  
Linear Sweep Voltammetry ◽  
Electrochemical Determination ◽  
The Other ◽  
Potential Range ◽  
Linear Sweep ◽  
Qualitative And Quantitative ◽  
Neutral Electrolyte

A gold electrode was used for the qualitative and quantitative electrochemical determination of analytical methomyl in a neutral electrolyte (0.050 M NaHCO3) using cyclic linear sweep voltammetry. In the potential range from -800 mV vs. SCE to 1000 mV vs. SCE the analytical methomyl was quantitatively determined in the concentration range 4.0-16 mg L-1. In the potential range from -1300 mV vs. SCE to 1300 mV vs. SCE, methomyl was qualitatively determined by two anodic and four cathodic reactions. Cycling the potential in this range for 150 min caused the degradation of the molecule, which was confirmed by HPLC analysis. On the other hand, technical methomyl exhibited an inhibition of the gold electrode surface due to the impurities.

Comparative Electrochemical Study of Some Phenothiazines with Carbon Paste, Solid Carbon Paste and Glass-Like Carbon Electrodes

2000 ◽  
Vol 65 (6) ◽  
pp. 1014-1028 ◽  
Author(s):  
Robert V. Sandulescu ◽  
Simona M. Mirel ◽  
Radu N. Oprean ◽  
Simion Lotrean
Keyword(s):  
Modified Electrodes ◽  
Linear Sweep Voltammetry ◽  
Pharmaceutical Formulations ◽  
Oxidation Potential ◽  
Electrochemical Study ◽  
Carbon Electrodes ◽  
Potential Range ◽  
Solid Carbon ◽  
Carbon Paste ◽  
Linear Sweep

In order to obtain modified electrodes with phenothiazines and to develop electrochemical methods for their determination in pharmaceutical formulations, promazine maleate, promethazine maleate and levomepromazine, were studied by linear sweep voltammetry using different types of working electrodes: carbon paste, solid carbon paste and glass-like carbon electrodes. A comparative electrochemical study of the above mentioned pheno- thiazines was performed in aqueous-alcoholic solutions, investigating the influence of pH, ionic strength and concentration on the current-potential curves. Linear sweep voltammetry in potential range from -0.1 to +1.3 V revealed that the oxidation potential and the current, strongly depend on the type of electrode and pH, the best results being obtained in acid buffer (pH 1.0). The current intensity depending linearly on the concentration in the range of 2.5·10-5-5·10-4 M promazine maleate, 2.5·10-5-2.5·10-4 M promethazine maleate and 6.2·10-5-1.2·10-3 M levomepromazine permits the development of electroanalytical methods to determine these phenothiazines in pharmaceuticals. The electrochemical determination yielded results comparable with spectrophotometric methods. Linear sweep voltammetry of carbon paste electrodes modified by incorporation of phenothiazines opens the possibility to use them as mediators in the design of some enzyme selective electrodes.

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