Organic compounds reduction and

In electroless deposition, the substrate, prepared in the same manner as in electroplating (qv), is immersed in a solution containing the desired film components (see Electroless plating). The solutions generally used contain soluble nickel salts, hypophosphite, and organic compounds, and plating occurs by a spontaneous reduction of the metal ions by the hypophosphite at the substrate surface, which is presumed to catalyze the oxidation—reduction reaction. 

In the present chapter we want to look at certain electrochemical redox reactions occurring at inert electrodes not involved in the reactions stoichiometrically. The reactions to be considered are the change of charge of ions in an electrolyte solution, the evolution and ionization of hydrogen, oxygen, and chlorine, the oxidation and reduction of organic compounds, and the like. The rates of these reactions, often also their direction, depend on the catalytic properties of the electrode employed (discussed in greater detail in Chapter 28). It is for this reason that these reactions are sometimes called electrocatalytic. For each of the examples, we point out its practical value at present and in the future and provide certain kinetic and mechanistic details. Some catalytic features are also discussed. 

An acidic bromate solution can oxidize various organic compounds and the reaction is catalyzed by species like cerous and manganous ions that can generate 1-equivalent oxidants with quite positive reduction potential. Belousov (1959) first observed oscillations in Celv]/[Cem] during Ce (III) catalysed oxidation of citric acid by bromate ion. Zhabotinskii made extensive studies of both temporal and spatial oscillations and also demonstrated that instead of Ce (III), weak 1- equivalent reductants like Mn(II) and Fe (II) can also be used. The reaction is called Belousov-Zhabotinskii reaction. This reaction, most studied and best understood, can be represented as... 

Relatively little is known about the speciation of organic compounds, and organic reductants in particular, when adsorbed to metal oxides. It is known that surface coverage is higher for bidentate organic ligands, such as catechol and salicylate, than... 

Additional emission reductions of benzene, volatile organic compounds, and particulate matter... 

ET to disulfides leads, as a rule, to the cleavage of the S—S bond by a stepwise mechanism. For the purposes of this review, we will focus only on the data obtained at inert electrodes, particularly glassy carbon electrodes. The reduction of the disulfide bond, in both simple organic compounds and... 

Tab. 8.5 Examples of reducible step in aprotic solvents organic compounds and the potential Is of their first reduction ...

As discussed elsewhere (212), the one-electron oxidation or reduction of, e.g., unsaturated hydrocarbons or other electroactive organic compounds and ions [Eqs. (37a)-(37d)] creates radical cations, radical anions, or radicals with an energy content, which surmounts that of the original substrate... 

Many organic compounds undergo reduction or oxidation at a DME. Consequently, polarographic techniques have been used extensively for determinations of organic compounds and for studying the mechanisms of their electrode reactions. In aqueous solution, the reduction of organic compounds is frequently a 2e process accompanied by protonation as in Equation 3.32 ... 

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