Electrode reactions of nitroxide radicals: Part 10. Kinetics and mechanisms of the redox reactions of the 2,2,6,6-tetramethylpiperidine-1-oxyl derivatives in acetonitrile solutions on the gold electrode. Experiment and simulation analysis

Abstract The redox reaction Nox . ← Nox + + e − of the 8 free nitroxide radicals, which are derivatives of 2,2,6,6-tetramethylpiperidine-1-oxyl, were investigated in acetonitrile solutions ( c = 2.5 × 10 −4 − 1 × 10 −2 mol dm −3 ) on a gold working electrode. Cyclic voltammetry (υ = 0.02–10.0 V s −1 ), impedance measurements and controlled potential electrolysis were used. The reaction parameters ( E ° f , D ox , α n ) and the Taft coefficients σ″ were calculated on the basis of the experimental results. The kinetics and the mechanisms of these processes are discussed, and a model of the reaction mechanism with weak adsorption of both forms of the reactants is proposed on the basis of the simulation analysis.