Zdenek Samec

The double layer at the interface between two immiscible electrolyte solutions

Journal of electroanalytical chemistry and interfacial electrochemistry, Sep 1, 1981

ABSTRACT

The double layer at the interface between two immiscible electrolyte solutions

Journal of electroanalytical chemistry and interfacial electrochemistry, Dec 1, 1983

ABSTRACT

Stochastic approach to the ion transfer kinetics across the interface between two immiscible electrolyte solutions comparison with the experimental data

Journal of electroanalytical chemistry and interfacial electrochemistry, Jun 1, 1986

The stochastic approach to the ion transfer kinetics across the interface between two immiscible ... more

Charge transfer between two immiscible electrolyte solutions Advances in method of electrolysis with the electrolyte dropping electrode (EDE)

Journal of electroanalytical chemistry, Jun 8, 1979

An electron transfer reaction O l ( w ) + R2(n) ~ R l ( w ) + O2(n) takes place at the boundary o... more An electron transfer reaction O l ( w ) + R2(n) ~ R l ( w ) + O2(n) takes place at the boundary of two immiscible phases: the aqueous (w) and the non-aqueous (n) electrolyte solutions, between the redox couple O1/R1 in the aqueous phase and the redox couple O2/R2 in the non-aqueous phase, Using the stationary Nernst-diffusion layer treatment and neglecting the migration and adsorption effects the relationship between the current and the electrical potential difference across the interface has been derived and analysed. The stationary curve of current vs. potential has some unusual properties which result from the coupling of the first order mass transport process in each phase with the second order electron transfer reaction at the interface: The method has been suggested for the analysis of the curve of mean current vs. potential of the electron transfer reaction at the electrolyte dropping electrode.

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Charge transfer between two immiscible electrolyte solutions Part II. The investigation of Cs+ ion transfer across the nitrobenzene/water interface by cyclic voltammetry with IR drop compensation

Journal of electroanalytical chemistry, Jul 1, 1979

The theoretical fundamentals of the kinetics of ion and electron transfer reactions at the interf... more

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ChemInform Abstract: Origin of Electrocatalysis in the Reduction of Peroxodisulfate on Gold Electrodes

ChemInform, Jun 24, 2010

Voltammetric study of the cyanide complexes of osmium—I. The reduction of the cyanide complex of Os(VI) on a platinum rde

Electrochimica Acta, Mar 1, 1977

Two forms of cyanide complexes of hexavalent osmium were found in alkaline KCN solutions. The ini... more Two forms of cyanide complexes of hexavalent osmium were found in alkaline KCN solutions. The initially formed complex, OsO1(OH),(CN):-, is stable only in solutions with at least a ten-fold excess of OH-ions over CN-ions. At higher cyanide concentrations it is converted into the OsO,(CN)~~ complex. Both these complexes are reduced to tervalent osmium. A more detailed study of complex OsO,(OH),(CN):-has shown that it is reduced electrochemically according to the scheme of a consecutive electrochemical reaction, OsO,(OH),(CN): -+ 2e&, , OLI) --* Os(IV) + e&,, ~1) --, Os(OH)',(CN): The values LY, = 0.65 and a3 = 0.40 and the potential dependences of constants kl and kz were determined. In the reaction of 0~0~ with alkali cyanide, octavalent osmium is reduced to hexavalent and a cyanide complex is formed. This complex has not yet been prepared in the solid state and its composition was determined[l] from the analysis of its sparingly soluble salts with copper and silver. It has been found that its composition corresponds to the formula, OsO,(CN)i-. The complex is remarkably stable; it is not even decomposed by boiling with mineral acids. Griffith[2] obtained the ir spectrum and found the important frequencies, v (O=Os==O) at 830 cm-' and v (C=N) at 2152 cm-'. reduced the cyanide complex of Os(VI) polarographically on a dme. It has been found that it is reduced in two steps and from coulometric measurements it followed that Os(V1) is reduced to Os(II1) in the first step and to Os(II) in the second. Meites assumed that the tervalent and divalent osmium thus obtained from hexavalent osmium form hexacyano-complexes. The E,,, value of the reversible reaction, Os(III)~ Os(II), was measured and this value, Eljz = -0.75 V/see is given in[5,6] as the value of the formal redox potential of the cell, Os(CN)i-/Os(CN)t-. However, it has been shown[7] that the redox potential of this system, determined from the dependence of the E,,, value for the oxidation of the prepared salt K,Os(CN), on the square root of the ionic strength, extrapolated to zero ionic strength, is substantially more positive

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2008年志方国際メダル受賞記念総説 A Note on the Standard Electron Transfer Potential at the Interface between Two Immiscible Electrolyte Solutions

ポーラログラフィー, Sep 28, 2009

The double layer at the interface between two immiscible electrolyte solutions

Journal of electroanalytical chemistry and interfacial electrochemistry, May 1, 1985

ABSTRACT

Kinetics of Charge Transfer

CRC Press eBooks, Nov 26, 2020

Charge transfer between two immiscible electrolyte solutions Part IV. Electron transfer between hexacyanoferrate(III) in water and ferrocene in nitrobenzene investigated by cyclic voltammetry with four-electrode system

Journal of electroanalytical chemistry, Oct 25, 1979

An electron transfer reaction O l ( w ) + R2(n) ~ R l ( w ) + O2(n) takes place at the boundary o... more An electron transfer reaction O l ( w ) + R2(n) ~ R l ( w ) + O2(n) takes place at the boundary of two immiscible phases: the aqueous (w) and the non-aqueous (n) electrolyte solutions, between the redox couple O1/R1 in the aqueous phase and the redox couple O2/R2 in the non-aqueous phase, Using the stationary Nernst-diffusion layer treatment and neglecting the migration and adsorption effects the relationship between the current and the electrical potential difference across the interface has been derived and analysed. The stationary curve of current vs. potential has some unusual properties which result from the coupling of the first order mass transport process in each phase with the second order electron transfer reaction at the interface: The method has been suggested for the analysis of the curve of mean current vs. potential of the electron transfer reaction at the electrolyte dropping electrode.

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The Modeling of the Interaction of Organic Molecules with Gold and Platinum Clusters

CRC Press eBooks, Oct 27, 2006

Kinetics of the Ion Transport through the new Types of Ion-Selective Membranes

Chemie Ingenieur Technik, Jun 1, 2001

談話室 History of the Ilkovic Equation

ポーラログラフィー, Dec 10, 2002

Origin of electrocatalysis in the reduction of peroxodisulfate on gold electrodes

Journal of Electroanalytical Chemistry, Jul 1, 1997

Stationary and rotating disc electrode voltammelry are employed to study the kinetics of the pero... more Stationary and rotating disc electrode voltammelry are employed to study the kinetics of the peroxodisulfitle reduction to sullhte on Au(110) and Au(I I I) electrodes in the I)erchloric acid solution. "i'lle su|'face and tl|e inlerl'acial structure of these electn~des are exalnined by ex-situ STM and impedance measurements, respectively. Strong adsorption of peroxodisulfate and/or sulthte on both surfaces is observed, which has the superequivalent character, and which is controlled mainly by the charge on the metal. The surface structure and symmetry of the Au(lll) surface allows for a more effective overlap of the electronic wave functions of the metal and the adsorbed peroxodisulfate, which results in a two order of magnitude faster electron transfer than on Au(i 10). On negatively charged surfaces, the rate of this electrocatalytic pathway is limited by the decreasing surface concentration of peroxodisulfate, while the rate of the electron transfer to the solution species (the direct pathway) can be measured. Its correction tbr the double layer effect reveals that the true kinetic parameters of the direct pathway have essentially the same values for both electrodes. A comparison of the kinetic behaviour of the flame-annealed and non-annealed Au(ll I) electrodes throws some light on the role of the steps on the metal surface. ¢_91997 Elsevier Science S.A.

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Charge transfer between two immiscible electrolyte solutions part VIII. Transfer of alkali and alkaline earth-metal cations across the water/nitrobenzene interface facilitated by synthetic neutral ion carriers

Journal of electroanalytical chemistry and interfacial electrochemistry, May 1, 1982

ABSTRACT

Charge transfer between two immiscible electrolyte solutions Part IX. Kinetics of the transfer of choline and acetylcholine cations across the water/nitrobenzene interface

Journal of electroanalytical chemistry and interfacial electrochemistry, Nov 10, 1983

Electrochemical and density functional studies of the catalytic ethylene oxidation on nanostructured Au electrodes

Catalysis Today, Dec 1, 2010

Electrocatalytic oxidation of ethylene on gold was investigated by means of differential electroc... more Electrocatalytic oxidation of ethylene on gold was investigated by means of differential electrochemical mass spectroscopy (DEMS), quartz crystal microbalance (QCM) and DFT calculations. The product analysis indicates a selectivity of the polycrystalline gold towards formation of acetaldehyde. The oxidation process on fresh surface prepared by surface gold oxide reduction, on the other hand, forms mainly carbon dioxide. The oxidation process

Mechanism of peroxodisulfate reduction at a polycrystalline gold electrode

Journal of Electroanalytical Chemistry, Mar 1, 1994

The reduction of peroxodisulfate anions at a polycrystalline gold electrode in various base elect... more The reduction of peroxodisulfate anions at a polycrystalline gold electrode in various base electrolytes (NaF, HClO4, H2SO4) was studied by rotating disc voltammetry and the a.c. impedance technique. The reaction proceeds via two parallel pathways: surface (catalytic) and direct charge transfer mechanisms, which involve chemically adsorbed and solution intermediates respectively. Specific adsorption of peroxodisulfate, and/or of the sulfate anion produced, results in a negative shift of the potential of zero charge Epzc, and in suppression of the electrostatic effect of the electrical double layer on the direct charge transfer at E >Epzc. On the negatively charged electrode surface, the electrostatic repulsion of peroxodisulfate anions from the electrical double layer is a significant kinetic factor which can be accounted for quantitatively using the classical Frumkin correction. In both acidic and neutral media, surface metal oxides play a minor role.

Electrolyte dropping electrode polarographic studies. Solvent effect on stability of crown ether complexes of alkali-metal cations

Analytical Chemistry, May 15, 1990

A simple three-electrode polarographic assembly with the electrolyte dropplng electrode for the s... more A simple three-electrode polarographic assembly with the electrolyte dropplng electrode for the study of the Ion transport across a IIquM-Hquid Interface was presented. Transfer of alkall-metal catlons from water to nltrobenzene (NB) or 1,2-dlddwoethane (1,2-DCE) facimatd by complex formation with dlbenzo-18trown-6, dlbenzo-24trown-8, or dlbenzo-30-crown-10 was studied. Experimental current vs potential data were used to clarlfy the mechanism of the ion transport and to evaluate the stablllty constants of crown ether complexes. The stabNlty constants are 105-107 larger in NB and 10'o-10'2 larger In 1,P-DCE than those In water. The selectlvlty sequence changes with the solvent, comparing water (K' > Na' > Rb' > Cs') wlth NB (Na' > K' > Rb' > Cs',

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