Analysis for voltammetric responses of molecular-solid tetrathionaphthalene confined on an electrode

The cyclic voltammetry (CV) of solid-state tetrathionaphthalene (TTN; particles with diameters from a few tens to hundreds of nanometers) confined on electrodes was analyzed quantitatively by considering the inert-zone potential, the thermodynamic and kinetic interactions, and the kinetics of the electrode reaction. Theoretical treatments are applied for clarifying the experimentally accessible corresponding parameters. From the potential of full peak width at half-height current (ΔE(p1/2)) and the peak current (i(p)) for the reversible CV voltammogram obtained at the slowest potential scan rate, the thermodynamic attraction forces in their active materials are evaluated as W = 3.67 ± 0.30 kJ mol(-1) for the (TTN)(0/1+) redox couple. From the shift of peak potential (ΔE(p)) and the changes in ΔE(p1/2) and/or the magnitude of i(p) for the irreversible CV obtained against the moderate potential scan rate, the value of the formal rate constant (k°') regarding surface electrode reaction of the (TTN)(0/1+) couple was evaluated as 0.59 ± 0.10 s(-1). The interaction parameters of W and ΔW[symbol: see text] being related to the thermodynamic and the kinetic interactions of the electrode reaction for the (TTN)(0/1+) couple were also evaluated as 3.39 ± 0.41 kJ mol(-1) and -1.39 ± 0.31 kJ mol(-1), respectively, from analysis for the irreversible CV.