Half-wave potential rotating electrode voltammetry

The current-potential relationship of the totally - irreversible electrode reaction Ox + ne - Red in the techniques mentioned above is I = IiKexp(-af)/ (1+ Kexp(-asteady-state voltammetry, a. is a - transfer coefficient, ks is -> standard rate constant, t is a drop life-time, S is a -> diffusion layer thickness, and

logarithmic analysis of this wave is also a straight line E = Eff + 2.303 x (RT/anF) logzc + 2.303 x (RT/anF) log [(fi, - I) /I -The slope of this line is 0.059/a V. It can be used for the determination of transfer coefficients, if the number of electrons is known. The half-wave potential depends on the drop life-time, or the rotation rate, or the microelectrode radius, and this relationship can be used for the determination of the standard rate constant, if the formal potential is known. 

The electron affinity of 3-(iV-methylpiperazino)-5-nitroindazole, 3,5-dinitroindazole, and molecular complex of the last with water is discussed on the basis of their half-wave potentials and in connection with their eventual radiosensitizing properties [667], The mechanism of EC behavior of 2-substituted 5(6)-nitrobenzimidazoles in acetonitrile has been investigated by classical polarography, cyclic voltammetry, and platinum rotating disk electrode with a ring (RDER) [888,991], It is shown that... 

Abbreviations are CV — cyclic voltammetry DMF — N,N-Dimethylformamide E swp — potential sweep E° — standard potential — peak potential E — half-peak potential E — half wave potential M — mol/L i eCN — acetonitrile pol — polarography rot Pt dsk — rotated Pt disk SCE — saturated calomel electrode TBABF — tetrabutylammonium tetrafluoroborate TBAl — tetrabutylammonium iodide TBAP — tetrabutylammonium perchlorate TEABr — tetraethylammonium bromide TEAP — tetraethylammonium perchlorate THF — tetrahydrofu-ran TPACF SO — tetrapropylammonium trifluoromethanesul-fite TPAP — tetrapropylammonium perchlorate and wr — wire. 

The half-wave potential of the catalytic wave for O2 reduction by rotating disk voltammetry. This value depends on the electrode rotation rate, bulk O2 concentration, pH, and in many cases on the scan rate, the amount of the adsorbed catalyst, and the nature of the supporting electrol5h e n.m. - not meaningful (no defined wave). 

The function I is called the pseudopolarogram [25,26]. It is constructed by plotting the peak current in anodic stripping voltammetry as a function of the accumulation potential, because the peak current is linearly proportional to the concentration of metal atoms in the mercury electrode [27]. The half-wave potential of a pseudopolarogram depends on the mercury film thickness, the electrode rotation rate and the duration of accumulation. It can be used for the estimation of the optimal accumulation potential [28]. Besides, if metal ions form labile complexes with ligands in the solution, the half-wave potential of a pseudopolarogram depends on the ligand concentration, so that the stability constant of the complexes can be determined from this dependence [29,30]. If... 

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