Electrochemical reductive cleavage of carbon tetrachloride in aqueous-nonaqueous binary solvents

A concerted dissociative electron transfer mechanism has been observed in the electrochemical reduction of carbon tetrachloride in N,N′-dimethyl formamide (DMF) - water binary solvent. The kinetics of the process deviate from Butler-Volmer kinetics with a linear dependence of the transfer coefficient on the potential. The standard electrode potentials of the process in various compositions of the binary mixture have been estimated using the voltammetric data coupled with convolution analysis and are in agreement with independent theoretical calculations. The variation of the transfer coefficient with the composition of the binary mixture has led to the investigation of the problem based on Marcus-Savéant dissociative electron transfer theory and the solvent reorganization energies for various compositions of the binary mixture have been evaluated using the above analysis. © 2004 Elsevier B.V. All rights reserved.