A Rate of Zinc Potentiostatic Nucleation on a Pyrolytic Carbon Electrode from an Alkaline Solution

Abstract

A method for calculation of an average local rate A¯ of potentiostatic nucleation in an arbitrary time range of an electrode process has been proposed. An example of analysis of Zn nucleation from a zincate electrolyte on a pyrolytic carbon electrode according to Scharifker and Mostany's kinetic model has been used as an illustration of the proposed method. A growth or decrease of A¯ during the nucleation period has been explained by activation of the electrode surface or depletion of more active center of the electrode, respectively.

Potentiostatic Nucleation of Zinc on a Pyrolitic Carbon Electrode from a Zincate Electrolyte Containing Polymeric Tetraalkylammonium Salt as an Additive

“…It is assumed ( 17) that higher experimental values of N s compared to calculated ones are bound up with an influence of slow charge transfer and energy inhomogeneity of an electrode surface on nucleation which are not taken into account by the model (15). Some aspects of that influence were analyzed in the works (13,19). In the study (18), disagreement between N s values is explained by overestimated dimensions of nucleation exclusion zones arisen from the law of nucleus growth assumed in the model (15).…”

Local Rate of Potentiostatic Nucleation of Zinc on Zirconium Electrode from Alkaline Solution

“…However, the study (4) was performed for the particular case of non-interacting diffusion fields of nuclei. In the case of such interaction, in our experimental research (6) we calculated the time-dependent values of the average local rate of nucleation Ā applying the model (7) based on constancy of A to a series of rising portions of a current transient I(t). In the present work we develop this approach to determine the average local nucleation rate Ā over a short time interval Δt in the vicinity of an arbitrary moment t of the electrode process.…”

Local Rate of Potentiostatic Nucleation of Zinc on Zirconium Electrode from Alkaline Solution

“…This conception was analyzed quantitatively in the work (4), however interaction of diffusion fields of nuclei was not considered, though this condition is hardly fulfilled experimentally. In case of such interaction, in the work (5) we presented a solution of the problem of nucleation rate dispersion determination by means of applying the model ( 6) based on a constant value of A to a series of portions of a current transient over time diapasons from t=0 to subsequent values of pulse times. In the present study, we develop this approach and propose to determine of a local nucleation rate Ā within time intervals at definite arbitrary moments of an electrode process.…”