Mechanism electroreduction

Electroreduction mechanisms and polarography of bicyclic N-heterocycles 85PHA81. 

SCHEME 2.4 Damjanovic s oxygen electroreduction mechanism with three electrochemical rate constants ki for the direct reduction to water, f°r the parallel formation of adsorbed hydrogen peroxide, and k3 for the electrochemical decomposition of hydrogen peroxide to water. The species with the super index and 0 are located at the interface and in the bulk of the solution, respectively. The term dif symbolizes the diffusion to the bulk of the solution and vice versa. 

The Most Likely Intermediate Species Involved in the Oxygen Electroreduction Mechanism on Pt(111) and Pt( 100) Clusters The adsorption configuration study for the oxygen adsorbates on platinum, described above, provides the possibility of exploring further mechanistic aspects of the oxygen electroreduction, particularly in relation to the possible species involved in the reaction that account for the different behavior of Pt(l 11) and Pt(100) electrode surfaces. 

Some Data on the Electroreduction Mechanisms of Polyvalent Species in... 

Solvent effects on the redox potentials and electroreduction mechanisms of (TPP)CrCl have been discussed by Bas-solo and Hoffman [151, 152], as well as by Bottomley and Kadish [153]. The former research group demonstrated that (TPP)CrCl can readily coordinate with Lewis bases containing oxygen, sulfur or nitrogen donor atoms to form six-coordinate Cr(III) species of the type (TPP)CrCl(L), while the latter group indicated that the Cr(III)/Gr(II) process was accompanied by chemical reactions coupled with reversible electron transfers. The current-voltage curves led the authors to propose the electron-transfer mechanism shown in Sch. 1. 

The compounds with X = OMe were relatively stable after reduction, but the compounds with X = CP were shown to undergo a series of chemical reactions following electron transfer. The ultimate stable porphyrin product of the reduction was proposed to contain a Sb(III) ion. The electroreduction mechanism of [(P)Sb(X)2]+ is illustrated in Sch. 14. 

A schematic course of the reaction is shown in Scheme 1, and as the authors point out, is not intended to represent the exact details of the electroreduction mechanisms. 

Uchiyama S, Muto G (1981) Dependence of pH and chelate ligand on the electroreduction mechanism of... 

In the above expression, the R represents the additive incorporation rate in flux units [mol m s ] and Q stands for concentration of the additive in the plating solution [mol m ]. The first term on the right side represents the additive incorporation via electroreduction mechanism and the second term represents the additive incorporation by physical entrapment of the entire molecules. The K and K2 are the electro reduction and incorporation rate constants expressed in [mol-m s ] units and b is the additive adsorption constant [m moP ]. The above model can predict the concentration of the different interstitials/inclusions in electrodeposited films originating from incorporated additives as well as to correlate the additive incorporation effect with the deposit 92... 

Study of the electroreduction mechanism of Sip4 in molten fluorides and selection of the most suitable solvent, as we know that SiF4 is a volatile compound [3] and that its stability is highly influenced by the fluoroacidity of the bath. 

Chebotin VN, Brainin MI, Soloviova LM, Pakhnutov lA, Lukach YS (1986) About the theory of solid oxide electrolytes electroreduction. Mechanism and kinetics of the process undo-galvanostatic blocking cathode. Elektrokhimiya (Rus) 22 158-163... 

A. Lasia, Applications of the electrochemical impedance spectroscopy to hydrogen adsorption, evolution and absorption into metals. Modem Aspects of Electrochemistry, B. E. Conway, R. White (Eds.), vol. 35, Kluwer Academic/ Plenum Publishers, New York, 2002, pp. 1-49. M. Itagaki, H. Hasegawa, K. Watanabe, T. Hachiya, Electroreduction mechanism of oxygen investigated by electrochemical impedance spectroscopy, J. Electroanal. Chem., 2003, 557, pp. 59-73. 

Heller-Ling, N., Prestst, M., Gautier, J.-L., Koenig, J.-F., Poillerat, G. and Chattier, P. Oxygen electroreduction mechanism at thin Ni.Covx04 spinel film in a double channel electrode flow cell (DCEFC) , Electrochim. Acta, 42 (1997) 197-202. 

---