Electrochemical Charging, Countercation Accommodation, and Spectrochemical Identity of Microcrystalline Solid Cobalt Hexacyanoferrate

Oxidized and reduced cobalt(II) hexacyanoferrates were fabricated and characterized in the presence of alkali metal (Li+, Na+, K+, Cs+) and Co2+ countercations. Formal potentials of hexacyanoferrate(III,II) redox reactions are sensitive to the choice of electrolyte cation, and they correlate well with the sizes of hydrated Li+, Na+, and K+. Electrochemical quartz crystal microbalance measurements clearly indicate that countercations, presumably...