Comments on the paper entitled ‘The formulation and modelling of the anodic dissolution of zinc through adsorbed intermediates’by G.G. Láng, and G. Horányi [J. Electroanal. Chem. 583 (2005) 148–154]
Abstract
The recent paper of Láng, and Horányi [1] is aimed at emphasising the problems raised by the use of kinetic models when applied to metal anodic dissolution. It could apply as well to electrocrystallization. However, these authors mainly made a critical review of results and conclusions presented in different recent papers dealing with the electrodissolution of metals in various aqueous media [2], [3], [4], [5], [6], [7], [8], [9], [10].
First of all, most of this paper (at least two pages) is a copy-paste from original papers [2], [3], [4], [5], [6], [7], for both the models proposed and the experimental results. This kind of models has been published in the last decades by many electrochemists. Among the most well-known are Bockris [11], [12], [13], Heusler [14], the groups of Thirsk in UK [15], [16], Épelboin in France [17], [18], Lorenz in Germany [19], [20] regardless of the techniques used, electrochemical impedance spectroscopy (EIS) or polarisation curves. Of course, these works have been the object of a series of controversies, dealing mainly with their speculative aspects with respect to the chemical nature of the adsorbed species, type of isotherms… Additional techniques, such as microgravimetry, spectro-electrochemistry eventually in the framework of the impedance concept, may contribute to enhance the chemical relevance of the models. However, the consistency of these models in terms of charge balance and conservation of the fluxes of electrical charges across the whole cell was never questioned.