Mechanism of the electrochemical oxidation

Tributyltin deuteride has also been used to help determine the mechanism of the electrochemical oxidation of carbonylmanganese phosphites and carbonylmanganese phosphines (equation 113). 

An alternative electrochemical method has recently been used to obtain the standard potentials of a series of 31 PhO /PhO- redox couples (13). This method uses conventional cyclic voltammetry, and it is based on the CV s obtained on alkaline solutions of the phenols. The observed CV s are completely irreversible and simply show a wave corresponding to the one-electron oxidation of PhO-. The irreversibility is due to the rapid homogeneous decay of the PhO radicals produced, such that no reverse wave can be detected. It is well known that PhO radicals decay with second-order kinetics and rate constants close to the diffusion-controlled limit. If the mechanism of the electrochemical oxidation of PhO- consists of diffusion-limited transfer of the electron from PhO- to the electrode and the second-order decay of the PhO radicals, the following equation describes the scan-rate dependence of the peak potential ... 

Appleby A.J. Pinchon B., The mechanisms of the electrochemical oxidation of sulphur dioxide in sulphuric acid solutions. Jal of Electroanalytical Chemistry, 95(1), pp. 59-71, 1979. 

Arvia, A.J., Triaca, W.E., and Videla, A.H. (1970). Kinetics and mechanism of the electrochemical oxidation of graphite in bisulphate melts. Electrochim. Acta, 15, 9-24. 

For better understanding of the mechanisms of the electrochemical oxidation of phenol a comparative study was undertaken between electrochemical (with Pt and Sn02 anodes) and chemical oxidation of phenol with H2O2 in the presence of Fe+2 catalyst (Fenton s reagent) which is well known to occur by electrophilic attack of hydroxyl radicals on the organic compound (8). 

The kinetics and mechanism of the electrochemical oxidation of D-glucose to D-gluconlc acid at a platinum electrode have been reported. ... 

Mechanism of the Electrochemical Oxidation (Mineralization) of Organics via the Intermediates of O2 Evolution Reactions... 

Two mechanisms can be distinguished for the electrochemical oxidation of organic compounds- direct oxidation and indirect oxidation via electrogenerated intermediates formed at the anode surface. Cyclic voltammetry has been used to investigate the mechanism of the electrochemical oxidation of two classes of organic compounds on BDD- ... 

RTILs have been useful for the sensing of ammonia and the mechanism of the electrochemical oxidation of ammonia has been extensively explored due to... 

The character of the oxide layers influences the kinetics and mechanism of the electrochemical reactions occurring on the platinum anode surface. The relation between the rate of oxygen evolution and oxide layer thickness is complex. In the region where the a-oxides exist, the reaction rate decreases with increasing oxide layer thickness. In the region where the P-oxides exist, the reaction rate depends little on oxide layer thickness or, according to some data, increases with increasing oxide layer thickness. 

Gilman S. 1964. The mechanism of electrochemical oxidation of carbon monoxide and methanol on platinum. II. The reactant pair mechanism for the electrochemical oxidation of carbon monoxide and methanol. J Phys Chem 68 70-80. 

Fig. 10. Mechanism of primary electrochemical oxidation of theobromine (1, R=H) and caffeine (I, R=CH3) at the PGE...

Fig. 16. Mechanism for the electrochemical oxidation of adenine at the PGE. Molar amounts of products are those formed in 1 M HOAc...

The kinetics of the electrochemical oxidation of ammonia on platinum to dinitrogen in basic electrolytes has been extensively studied. In the widely supported mechanism originally suggested by Gerischer and Mauerer[ll], the active intermediate in the selective oxidation to N2 is a partly dehydrogenated ammonia adsorbate, NH2 ads or NHaatomic nitrogen adsorbate N ag, which is apparently formed at more positive potentials, is inactive toward N2 production at room temperature. Generally, only platinum and iridium electrodes exhibit steady-state N2 production at potentials at which no sur-... 

The importance of 1,4-dihydropyridine nucleotides in biological systems prompted the increasing interest in their electrochemical oxidation.238-243 The mechanistic aspects of the electrochemical oxidation of NADH involving removal of two electrons and one proton to form NAD4 has been examined in aqueous and DMSO media at a glassy carbon electrode.242 The reaction occurs according to an ECE mechanism ... 

The mechanism of the reaction of thiophene with a variety of radicals as a function of pH has been studied using ESR (81JCS(P2)207). Attack by -OH at pH 6 proceeds by direct addition with a preference to add to the a-position the ratio of (226) to (227) is 4 1. At low pH the (3-adduct easily loses OH- to form the thiophene radical-cation, which may undergo rehydration. In the case of 2-methyIthiophene the radical-cation deprotonates to give the thenyl radical this is reminiscent of the electrochemical oxidation (Section 3.14.2.6). The radical-cations are also formed by direct electron abstraction from the thiophene substrates by chlorine anion-radicals. At pH >6, (226) starts disappearing with formation of ring-opened products (Scheme 61). 

The electrochemical oxidation of model compounds of NADH in acetonitrile gives two main oxidation peaks in the absence of a base, clearly demonstrating a stepwise oxidation of NADH (41). An ECE (electrochemical-chemical-electrochemical) mechanism for the electrochemical oxidation of NADH has been proposed in several studies (41-47) most often depicted ... 

Camara, G.A. et al.. The CO poisoning mechanism of the hydrogen oxidation reaction in proton exchange membrane fuel cells, J. Electrochem. Soc., 149, A748, 2002. 

In recent years, there has been a growing interest in the electrochemical synthesis of composite materials consisting of metal matrix with embedded particles of oxides, carbides, borides, etc. Metal-matrix composites offer new possibilities in fabrication of ftmctional coatings with radically improved durability and performance [1], However, in spite of the efforts of many researches, the overall picture of the processes occurring during co-deposition of metal with dispersed phase and mechanism of particle-induced modification of mechanical and chemical properties still remain unclear. In this study, we focused on the kinetics and mechanism of the electrochemical co-deposition of nickel with highly dispersed oxide phases of different nature and morphology. 

---