Effect of electrode surface

K. Chattopadhyay and S. Mazumdar, Direct electrochemistry of heme proteins effect of electrode surface modification by neutral surfactants. Bioelectrochemistry 53, 17-24 (2000). 

Electroanalytical chemists and others are concerned not only with the application of new and classical techniques to analytical problems, but also with the fundamental theoretical principles upon which these techniques are based. Electroanalytical techniques are proving useful in such diverse fields as electro-organic synthesis, fuel cell studies, and radical ion formation, as well as with such problems as the kinetics and mechanisms of electrode reactions, and the effects of electrode surface phenomena, adsorption, and the electrical double layer on electrode reactions. 

Figure 3. Effect of electrode surface contact in the solution on the potential.

Bouazaze, H., Cattarin, S., Huet, F. et al. (2006) Electrochemical noise study of the effect of electrode surface wetting on the evolution of electrolytic hydrogen huhhles. Journal of Electroanalytical Chemistry, 597, 60-68. 

Aureli M, Porfiri M (2012) Effect of electrode surface roughness on the electrical impedance of ionic polymer-metal composites. Smart Mater Struct 21 105030 Aureli M, Lin W, Porfiri M (2009) On the capacitance-boost of ionic polymer metal composites due to electroless plating theory and experiments. I Appl Phys 105 104911 Bard AJ, Falkner LF (2001) Electrochemical methods fundamentals and applications, 2nd edn. Wiley, New York... 

Fig. 2.18 The effect of electrode surface profile on the tertiary current distribution showing the size of the surface roughness x compared to the Nernstian diffusion layer thickness (5 and the relative limiting-current density 7l on the peaks and valleys.

The dependence of the C,E curves for a solid metal on the method of electrode surface preparation was reported long ago.10 20 67 70 219-225 in addition to the influence of impurities and faradaic processes, variation in the surface roughness was pointed out as a possible reason for the effect.10 67,70 74 219 For the determination of R it was first proposed to compare the values of C of the solid metal (M) with that of Hg, i.e., R = C-M/c-Hg 10,74.219-221 data at ff=0 for the most dilute solution (usually... 

Table 26 shows some steps in the chronological sequence of compilations, which are evidently related to improvements in the preparation and control of electrode surfaces. In second order, the control of the cleanliness of the electrolyte solution has to be taken into consideration since its effect becomes more and more remarkable with solid surfaces. A transfer of emphasis can in fact be recognized from Hg (late 1800s) to sp-metals, to sd-metals, to single-crystal faces, to d-metals, although a sharp chronological separation cannot be made. 

In spite of the importance of having an accurate description of the real electrochemical environment for obtaining absolute values, it seems that for these systems many trends and relative features can be obtained within a somewhat simpler framework. To make use of the wide range of theoretical tools and models developed within the fields of surface science and heterogeneous catalysis, we will concentrate on the effect of the surface and the electronic structure of the catalyst material. Importantly, we will extend the analysis by introducing a simple technique to account for the electrode potential. Hence, the aim of this chapter is to link the successful theoretical surface science framework with the complicated electrochemical environment in a model simple enough to allow for the development of both trends and general conclusions. 

Wagner FT, Ross PN. 1983. T, EF.D analysis of electrode surfaces—Structural effects of poten-tiod3mamic cychng on Pt single-crystals. J Electroanal Chem 150 141-164. 

The central issue which has to be addressed in any comprehensive study of electrode-surface phenomena is the determination of an unambiguous correlation between interfacial composition, interfacial structure, and interfacial reactivity. This principal concern is of course identical to the goal of fundamental studies in heterogeneous catalysis at gas-solid interfaces. However, electrochemical systems are far more complicated since a full treatment of the electrode-solution interface must incorporate not only the compact (inner) layer but also the boundary (outer) layer of the electrical double-layer. The effect of the outer layer on electrode reactions has been neglected in most surface electrochemical studies but in certain situations, such as in conducting polymers and... 

It has been known that adsorption kinetics and/or thermodynamics of proteins depend on the electric or electrochemical properties of solid supports on which the proteins are adsorbed. This has led us to elucidate the effects of electrode potential on the adsorption behavior of avidin on the electrode surface. For this purpose, the electrode potential of a Pt electrode was varied systematically in the range of -0.5-+2.0 V in an avidin solution (pH 7.4). Although the data was somewhat scattered, a general trend was observed that the adsorption of avidin is suppressed by the application of a positive potential (+1.0-+2.0 V). This may be originating from the fact that avidin is a basic protein and has net positive charges in the solution of neutral pH. In the potential range tested, no significant acceleration in the adsorption was induced. 

It should be noted that dielectric and optical properties of the near-the-surface layer of a semiconductor, which vary in a certain manner under the action of electric field, depend also on the physicochemical conditions of the experiment and on the prehistory of the semiconductor sample. For example, Gavrilenko et al (1976) and Bondarenko et al. (1975) observed a strong effect of such surface treatment as ion bombardment and mechanical polishing on electroreflection spectra. The damaged layer, which arises in the electrode due to such treatments, has quite different electrooptic characteristics in comparison with the same semiconductor of a perfect crystalline structure (see also Tyagai and Snitko, 1980). 

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