ELECTROCHEMICAL STUDY OF THE FE(III)-FE(II) ELECTRODE-REACTION IN THE ALUMINUM-CHLORIDE + N-(NORMAL-BUTYL)PYRIDINIUM CHLORIDE MOLTEN-SALT SYSTEM

The Fe(III)/Fe(II) electrode reaction was studied in the room temperature molten salt 2:1 molar ratio aluminum chloride+N-(n-butyl)pyridinium chloride at 30°C and in the 1:1 molar ratio aluminum chloride+N-(n-butyl)pyridinium chloride melt at 35°C. Techniques employed for this study were rotating disc electrode voltammetry, cyclic voltammetry and potentiometry. The results obtained in the 2:1 melt indicate that the charge transfer for reduction of Fe(III) is only moderately rapid (quasi-reversible) at glassy carbon and tungsten electrodes. In contrast the rate of reduction of Fe(III) appears to be mass transport controlled in 1:1 melt at these electrodes. Values of the standard heterogeneous rate constant, transfer coefficient, diffusion coefficient, and standard potential are reported for the Fe(III)/Fe(II) system. © 1979 Elsevier Sequoia S.A.