Electrochemical processes magnetic effects

Fahidy, T.Z. The Effect of Magnetic Fields on Electrochemical Processes 32... 

Lionbashevski et al. (2007) proposed a quantitative model that accounts for the magnetic held effect on electrochemical reactions at planar electrode surfaces, with the uniform or nonuniform held being perpendicular to the surface. The model couples the thickness of the diffusion boundary layer, resulting from the electrochemical process, with the convective hydrodynamic flow of the solution at the electrode interface induced by the magnetic held as a result of the magnetic force action. The model can serve as a background for future development of the problem. 

Refs. [i] Fahidy TZ (1999) The effect of magnetic fields on electrochemical processes. In Conway BE, Bockris JO M, White RE (eds) Modern aspects of electrochemistry, vol 32. Kluwer/Plenum, New York, pp 333-354 [ii] Fahidy TZ (2001) Progr Surf Sci 68 155 [Hi] Special issue on magnetic effects in electrochemistry (2007) Solid State Electrochem 11 677-756... 

Fahidy, T.Z. 1983. Magnetoelectrolysis. Journal of Applied Electrochemistry 13, 553-653. Fahidy, T.Z. 1999. The effect of magnetic fields on electrochemical processes. In Modern... 

Application of magnetic micro/nanoparticles and nanorods to achieve switchable electrode interfacial properties was described with examples above (see Section 18.4). This approach is still waiting to reach its pinnacle of future use in fiiel/BFCs. Another approach to the magnetic control of electrochemical reactions is based on the magnetohydrodynamic effect, which is well known for simple inorganic electrochemical processes [112-116], but it is rarely applied in bioelectrochemistry [117]. Recent development of the theory quantitatively describing the mechanism of the magnetohydrodynamic effect allowed its effective application in complex bioelectrocatalytic systems and BFCs [117-120]. 

Lioubashevski O, Katz E, WiUner I. Magnetic field effects on electrochemical processes a theoretical hydrodynamic model. J Phys Chem B 2004 108 5778-5784. 

Effects of Magnetic Processing on the Morphological, Electrochemical, and Photoelectrochemical Properties of Electrodes Modified with Cgo-Phenothiazine Nanoclusters... 

We examined the effects of magnetic processing on the morphological, electrochemical, and photoelectrochemical properties of electrodes modified with nanoclusters of CfioN and MePH (Figure 15.4) using a strong magnetic field [49]. 

Yonemura, H., Wakita, Y, Kuroda, N., Yamada, S., Fujiwara, Y. and Tanimoto, Y. (2008) Effects of magnetic processing on electrochemical and photoelectrochemical properties of electrodes modified with C )-phenothiazine nanoclusters. ]pn. J. Appl. Phys., 47, 1178-1183. 

It follows from Equation 6.12 that the current depends on the surface concentrations of O and R, i.e. on the potential of the working electrode, but the current is, for obvious reasons, also dependent on the transport of O and R to and from the electrode surface. It is intuitively understood that the transport of a substrate to the electrode surface, and of intermediates and products away from the electrode surface, has to be effective in order to achieve a high rate of conversion. In this sense, an electrochemical reaction is similar to any other chemical surface process. In a typical laboratory electrolysis cell, the necessary transport is accomplished by magnetic stirring. How exactly the fluid flow achieved by stirring and the diffusion in and out of the stationary layer close to the electrode surface may be described in mathematical terms is usually of no concern the mass transport just has to be effective. The situation is quite different when an electrochemical method is to be used for kinetics and mechanism studies. Kinetics and mechanism studies are, as a rule, based on the comparison of experimental results with theoretical predictions based on a given set of rate laws and, for this reason, it is of the utmost importance that the mass transport is well defined and calculable. Since the intention here is simply to introduce the different contributions to mass transport in electrochemistry, rather than to present a full mathematical account of the transport phenomena met in various electrochemical methods, we shall consider transport in only one dimension, the x-coordinate, normal to a planar electrode surface (see also Chapter 5). 

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