| Summary: | Cyclic voltammetric experiments were carried out on Li+, Na +, K+, Rb+ and Cs+ in ionic liquids (ILs). Alloy formation was noted at Pt microelectrodes, but not at Ni. A range of ILs was investigated to identify the best IL to study the M/M+ redox couples, and bulk electrodeposition of all metals was observed in at least one IL, N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([C4mpyrr] [NTf2]). Mathematical simulation of the CVs in this IL was conducted as a function of temperature. The diffusion coefficients, D, of the five metal ions were determined. The formal potential, E f0 (vs. Fc/Fc+) of the five M/M+ couples was quantified, as well as the electrochemical rate constants, k 0, and transfer coefficients, α. The activation energies of diffusion, Ea,dif, of Li+ and Na+ ions, and electron transfer, Ea, of Li/Li+ and Na/Na+ were determined, and ΔS0 (vs. Fc/Fc+) estimated for the Na/Na+ couple. The trends within the group are discussed. ©The Electrochemical Society.
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