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Laboratoire d'Electrochimie Moleculaire, LEM, Paris

UMR CNRS - Université Paris Diderot - Paris France

   
 
Master Frontiers in Chemistry | UFR de Chimie - Université Paris Diderot - Paris 7 CNRS - Institut de chimie Université de Paris Master Chimie Sorbonne Paris Cité UFR de Chimie - Université Paris Diderot - Paris 7 CNRS - Institut de chimie
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Université Paris Diderot
Université de Paris CNRS, Centre National de la Recherche Scientifique
 
 


Le LEM - Publications: Abstracts

Publication 631

Chem. Rev. 108, 2622– 2645, 2008.
DOI: 10.1021/cr0680787
 

Electron transfer in DNA and in DNA related biological processes. Electrochemical insights

Jean-Michel Savéant

Laboratoire d’Electrochimie Moléculaire, Université Paris Diderot Paris 7, UMR CNRS 7591, 2 place Jussieu, 75251 Paris Cedex 05, France,

 


Introduction - 1.1. \"Electrocatalysis\" and Molecular Catalysis

Scheme 1

Electrochemical reactions often require an important overpotential to proceed at an appreciable rate. This is particularly true when the reaction does not merely consist of an outersphere electron transfer between the electrode and a reactant but gives rise to bond breaking and bond formation, involving more than one reactant and one product, which may trigger the uptake or release of additional electrons, as sketched in Scheme 1.


This is a typical situation where catalysis of the electrochemical reaction is sought in order to increase the reaction rate and hence the current at a potential as close as possible to the equilibrium potential. Several strategies can be envisaged to achieve this goal. The term \"electrocatalysis\" is traditionally used for reactions in which the electrode material—often, but not always, a metal—is chemically involved in the catalytic process. Although the chemical properties of the electrode material play an important role in governing the catalytic efficiency, geometric and crystallographic features, nature and number of defects, may also be of paramount significance. The differences between the bulk properties of the metal and its surface properties are particularly important in this respect. It is therefore difficult, or even irrelevant, to analyze results and devise new catalytic systems on the basis of molecular concepts.

Figure 1

 

Another approach to catalyzing electrochemical reactions is to use molecules as catalysts. \"Molecular catalysis\" thus defined may involve catalyst molecules either homogeneously dispersed in the solution bathing the electrode or immobilized in a monolayer or multilayered coating deposited on the electrode surface as sketched in Figure 1 .

 

 

 

In line with the general theme of this special issue, this review is mostly concerned with molecular catalysis. Nevertheless, discussion of examples of electrocatalysis will not be systematically excluded. Analysis of the similarities and differences between electrocatalysis and molecular catalysis of the same global reaction may indeed benefit from the understanding of the mechanism in each case.

 
   
 
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