Electrode surface roughness

Nevertheless, despite the fact that the theory [84] looks convincing, we think it doubtful that the electrode surface roughness alone, without any additional conditions imposed, should not only cause the frequency dispersion of the capacitance, but also provide for its characteristic potential dependence, described by the Schottky theory. Moreover, a well-substantiated conclusion was drawn recently that the roughness of electrode surface does not necessarily cause the emergence of a CPE in the electrode s impedance [88],... 

For n = 1-e, where 0electrode surface roughness or distribution/accumulation of charge carriers. For n = 0.5 e, where 0< < 0.1, the CPE is related to diffusion, with deviations from Fick s second law. For n = 0 e, where 0inductive energy accumulation. Therefore, the CPE is a generalized element. Several factors can contribute to the CPE surface roughness, varying thickness or composition, non-uniform current distribution, and a distribution of reaction rates (non-homogeneous reaction rates on the electrode surface) [3],... 

Electrodes. The first observations of SERS were made from species on silver electrodes. An essential prerequisite for a strong SERS signal from molecules adsorbed on the electrode, surface roughness, is obtained by running electrochemical oxidation-reduction cycles (ORC) (Chang and Laube, 1984 Koglin and Sequaris, 1986 Roth et al., 1993). During the oxidation half cycle a metal salt, usually a halide, is formed at the electrode surface ... 

Then, (7) modified with (68) can be used for calculation of the polarization curves for the same electrochemical process at different values of electrode surface roughness at low level of coarseness. 

The electrode surface roughness at low level of coarseness can be increased in some different ways other than dendrites (spongy-like deposit,33 honeycomb-like structure,76,77 pyramid-like deposit,83 etc.) on the microscale. The properties of electrodeposits on nanoscale should be also taken into consideration.84,85 Further investigation will show which one of them is the best for this purpose. This chapter is written in order to initiate it. 

The detachment of the bubble occurs if the condition FB = Fc is satisfied. It follows that the mean bubble departure radius (Rd) is well defined for a given electrode—electrolyte configuration (typical values are around 50 pm [115]). It may be expected that the mean bubble departure radius is mainly a property of the electrode (the electrode surface roughness which influences D), the electrode wettability (through the contact angle i9), and the electrolyte (density and surface tension of the electrolyte), but not of the current density j. However, the question is whether a cavity (nucleation site) is active or non-active. The current density may influence the activation of the nucleation sites. 

Uniform Model of Solid Electrodes. Surface Roughness... 

Cgc cannot be used to determine the electrode surface roughness or the compact-layer capacitance ... 

For level 2, a thick paste at solid content is most suitable to disperse the active material. The electrode surface roughness can be used as an index to show the graphite dispersion state in electrode paint. Figure 7.7 shows the relationship between the solid content of thick paste and the surface roughness of the electrode. We think that smaller surface roughness and higher concentration of thick paste lead to a better dispersion of the mix. 

Fig. 7.7 Solid content and electrode surface roughness when kneading into thick pasted Reproduced by permission of CMC Publishing Co. Ltd...

Popov KI, Nikolic ND, Zivkovic PM, Brankovic G (2010) The effect of the electrode surface roughness at low level of coarseness on the polarization characteristics of electrochemical processes. Electrochim Acta 55 1919-1925... 

Electrode surface roughness, which must be reduced for better electrolytic deposition. 

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... 

It becomes important to highlight that, unlike for liquid eleetrodes, speeially mercury, for solid electrodes, the electroactive surfaee and its catalytic response depends directly on the effectively available area of such material. While for mercury electrode surface roughness has... 

Accounting an electrode surface roughness effect. The role of the surface roughness is analyzed by an example of a planar electrode assuming that the kinetic control belongs to the... 

In this chapter a generalized theory of the anodic voltammetry of a homogeneous A,B-alloy selective dissolution is developed taking into accormt the main peculiarities of the process. The diffusion problem of kinetically reversible dissolution at comparable rates of mass transfer in the liquid and solid phases is solved analytically. The conditions for the realization of purely liquid-phase and solid-phase diffusion transport in potentiodynamic alloy ionization are established. It is foimd that the higher ionic A concentration, lower scan rate and lower A concentration in an alloy contributes to the solid-phase diffusion regime of A dissolution. The effects of an equilibrimn solid phase adsorption of the components and electrode surface roughness with imiformly and statistically normal distribution of various... 

In one pathway, methanol is decomposed to form adsorbed CO, which can be further oxidized to CO2 at potentials higher than 0.5 V. In others, methanol is oxidized to formaldehyde, formic acid, and methyl formate. These soluble intermediates can be further oxidized to CO2 under some conditions. The extent of further oxidation of the soluble intermediates depends on convection (flow rate), electrode surface roughness and catalyst loading. 

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