Kinetics of CT reactions at the nano-ITIES

1 Mass-transfer and CT kinetic measurements at nano-ITIES 

In the case of simple IT (Eq. 1.1), the asymmetry of the diffusion field at a pipet-based ITIES, where the diffusion inside a narrow shaft is essentially 

Another issue complicating kinetic analysis of rapid CT reactions is a weak dependence of the shape of an almost reversible steady-state voltammogram on kinetic parameters and, consequently, the lack of the unique fit between the theoretical and experimental curves. The possibility to fit the same experimental curve using different combinations of k and a leads to significant uncertainties in extracted parameter values. This problem was addressed by using common ion voltammetry (see Seetion 1.3.4). 

Steady-state voltammetry was used to investigate ET reactions at the polarizable ITIES formed at the tip of 50-nm to 400-nm radius pipets. The pipet was filled with aqueous solution containing a mixture of two forms of redox species (Oi and Rj) and immersed in organic solution containing water-insoluble redox species (02)- The application of a sufficiently negative potential to the internal reference electrode with respect to the external (organic) reference resulted in the electric current across the nano-ITIES 

An extensive set of data was obtained for the TCNQ reduction by Fe(EDTA) in the following cell  

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