RATE CONSTANTS FUR THE ELECTRODE REACTIONS OF QUINONES IN CHLOROFORM: THE DEPENDENCE ON ELECTRODE MAmRIAL,S AND APPARENT STANDARD POENTIALS

Abstract

The reduction process for some quinones has been studid by cyclic voltammeby, rotating disk electrode voltammetry and chronopotentiometry in chloroform at platinum, gold and glassy carbon electrodes using tetrabutylmonium perchlorate (TB AP) as supporting eiectrolyte. The results obtained from this study reveal that the reduction of the quinones is two one-electron processes, the first reduction to the serniquinone anion radical is nearly reversible and the second to the dianion is quasireversib'te. The Gnetic parameters for the reduction of the quinones to the semiquinone were evaluated and the dependence on the electrode marerials and apparent standard potentiai is discussed. The diffusion coefficients of the quinones were determined from both chronopotentiometric and chronoamperomeMc measwements in 0.5 M chloroform solution of TBAP