Kinetics of ion transfer

Table III suggests some of the proton transfer kinetic studies one is likely to hear most about in the near future. The very first entry, colloidal suspensions, is one that Professor Langford mentioned earlier in these proceedings. In the relaxation field, one of the comparatively new developments has been the measurement of kinetics of ion transfer to and from colloidal suspensions. Yasunaga at Hiroshima University is a pioneer in this type of study (20, 21, 22). His students take materials such as iron oxides that form colloidal suspensions that do not precipitate rapidly and measure the kinetics of proton transfer to the colloidal particles using relaxation techniques such as the pressure-jump method.

In Chapter 7 general kinetics of electrode reactions is presented with kinetic parameters such as stoichiometric number, reaction order, and activation energy. In most cases the affinity of reactions is distributed in multiple steps rather than in a single particular rate step. Chapter 8 discusses the kinetics of electron transfer reactions across the electrode interfaces. Electron transfer proceeds through a quantum mechanical tunneling from an occupied electron level to a vacant electron level. Complexation and adsorption of redox particles influence the rate of electron transfer by shifting the electron level of redox particles. Chapter 9 discusses the kinetics of ion transfer reactions which are based upon activation processes of Boltzmann particles. 

Electrode Kinetics of Ion-Transfer (Deposition-Type) Reactions. 261... 

Nahon 117 from DuPont Chemical Co. was found to be the most effective membrane in terms of kinetics of ion transfer. The equilibrium isotherm showed that the membrane had a high selectivity for trivalent aluminum ions. This resulted in a rectangular isotherm for the Nahon 117 membrane. 

Kinetics of Ion-transfer Reactions Based on the Assumption of an Activated Ion-transfer Event... 

In a model put forward by Indenbom, the ITIES is considered as an elastic film in which forces of interfacial tension counteract the forces of an external electric field [64]. This causes a potential-dependent compressed grooved structure of the interface at which ion transfer takes place when the compression reaches a critical state. The validity of this picture will rely on detailed molecular dynamics studies of the microscopic features of ion transfer across ITIES. In this connectionit is relevant to mention the work of Cunnane and coworkers in which the kinetics of ion transfer across a monolayer adsorbed at a liquidjliquid interface is discussed in terms of the energy required to form a pore of a size similar to that of the transferring ion [56]. 

Cullane, V.J., Schiffrin, D.J., Fleischmann, M. et al. (1988) The kinetics of ion transfer across adsorbed phospholipid layers. Journal of Electroanalytical Chemistry, 243,455. 

The kinetics of ion transfer across ITIES is closely linked to the double-layer structure. The concentration of the ion transferred in each phase close to the plane dividing the both phases is related to the concentration outside the space charge region by the Boltzmann formula, for example, for the aqueous phase (cf. [9])... 

Murtomaki, L., K. Kontturi, and D. J. Schiffrin, Some remarks on the double layer correction to the kinetics of ion transfer at the interface of immiscible eleetrolytes,... 

The kinetics of ion transfer for the anodic and cathodic process can be formulated in terms of the transition state theory by the following equations. For the situation of Aq> = 0 ... 

Nanopipettes also are employed within SECM experiments to study the kinetics of ion transfer across an interface between two immiscible electrolyte solutions (ITIES). - In these experiments, the nanopipette is filled with an electrolyte solution that is immiscible with the surrounding bulk environment, and the current is measured as ions pass through the nanopore at the tip (Figure 11.16B). 

Wang Y, KaMuchi T, Yasui Y, Mirkin MV (2010) Kinetics of ion transfer at the ionic liquid/ water nanointerface. J Am Chem Soc 132(47) 16945-16952. doi 10.1021/jal066948... 

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