Metal/Metal Ion Electrodes with Two Charge-Transfer Steps: Me[sub x]-Alloy∕Me[sup z+] and Me[sup z+]∕Me[sup (z+1)+] Potentiostatic Transients under Charge-Transfer and Diffusion Control

Abstract

A theoretical treatment of the transients obtained in potentiostatic single pulse experiments on metal alloy/metal ion electrodes coupled to a redox reaction is presented. Formulas have been derived for the concentration of the electrochemically active component in the alloy and of the corresponding metal ions of different valent state which form the redox couple in the electrolyte, respectively, as a function of the distance from the interface and the duration of the voltage pulse. Expressions for the partial current densities carried by the two consecutive charge-transfer reactions, Me = Me z+ + zeand Me ~ § = Me (z+D § + e-, and for the total current density flowing through the cell have been worked out. Analysis of the current density transients on the basis of these expressions allows interpretation of experimental curves in terms of the characteristic kinetic parameters of the electrochemical system. ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 139.80.123.34 Downloaded on 2015-07-02 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 139.80.123.34 Downloaded on 2015-07-02 to IP

Electrochemical Reactions with Consecutive Charge-Transfer Steps: Steady-State and Time-Dependent Behavior under Charge-Transfer and Diffusion Control

“…vs. time curves discussed in Ref. (62,63) at 100, 150, 200, and 250 mV delayed maxima appear. Note that due to limitations by convection and by the finite rise time of electronic potentiostats the electrode process can be described in terms of the model discussed in this paper only within a time range 10 -5 --t ~ 1 sec.…”

“…Note that in a chronoamperometr~c study of the reduction of p-nitrosophenol Alberts and Shain (64) discussed the ECE case but with different b.c. as used in Ref (62,63). since only one substance was assumed to be present at t = 0 in their treatment.…”

Kinetics of Hydrogen Oxidation in Molten Carbonate: Application of Computer Curve‐Fitting Technique

“…Recently, more attention has been devoted to multistep electrochemical reactions. Electrode reactions with two consecutive charge transfer steps were analyzed by Bachmann and Bertocci for pure metal/metal-ion (10) and for alloy/metalion (11) systems under mixed control conditions. Because of the increasing mathematical complexity, the authors had to simplify their problems considerably in order to obtain analytical solutions; nevertheless the solutions were still too comblicated for a straightforward calculation of the kinetic current.…”