Electron transfer at metal electrodes

Santos E, Koper MTM, Schmickler W. 2006. A model for bond-breaking electron transfer at metal electrodes. Chem Phys Lett 419 421-425. 

Hale, J. M. The Rates of Reactions Involving Only Electron Transfer at Metal Electrodes, in Reactions of Molecules at Electrodes, Hush, N. S., Ed., Wiley New York, 1971, pp. 229-257. 

Fig. 8-8. Diffusion of redox particles before and after electron transfer at metal electrode i (i ) = cathodic (anodic) electron transfer current, t fr (>dfr) = cathodic (anodic) difiusi

Before considering the kinetics of photoelectrochemical reactions, it is useful to compare electron transfer at metal electrodes with electron trans-... 

The theoretical treatment of electron transfer at metal electrodes has much in common with that for homogeneous electron transfer described in 12.2.3. The role of one of the reactants is taken by the electrode surface, which provides a rigid two-dimensional environment where reaction occurs. In some respects, electrode reactions represent a particularly simple class of electron-transfer reactions because only one redox center is required to be activated prior to electron transfer, and the proximity of the electrode surface often may yield only a weak, nonspecific influence on the activation energetics of the isolated reactant. As with homogeneous electron transfer, it is useful to consider that simple electrochemical reactions occur in two steps (1) formation from the bulk reactant of a precursor state with the reacting species located at a suitable site within the interphasial region where electron transfer can occur (2) thermal activation of the precursor species leading to electron transfer and subsequent deactivation to form the product successor state. 

Hale J. M. (1971), Rates of reactions involving only electron transfer at metal electrodes , Ch. 4 inReactions of Molecules at Electrodes, HushN. S., ed., Wiley-Interscience, London, pp. 229-257. 

As studied by Bard and co-workers, the chemiluminescence of Ru(bipy)3 can be observed by electron transfer at metal electrodes when alternatively polarizing the Pt electrode between potentials corresponding to the redox potentials of Ru /Ru and Ru VRu [60]. The emission was interpreted as an electron transfer according to the reaction ... 

C J. Miller, Homogeneous electron transfer at metallic electrodes, in Physical Electrochemistry, Principles, Methods and Applications (ed. I. Rubinstein), Monographs in Electroanalytical Chemistry and Electrochemistry, Marcel Dekker, New York, 1995, p. 27. 

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