Potentiostatic reversible reaction when both reactant and product are adsorbed at the dropping mercury electrode Part I. Theoretical treatment

Abstract

The theoretical treatment of diffusion-limited, reversible electrode reactions with adsorption of reactant and/or product of the reaction under potentiostatic conditions, developed by Reinmuth and Balasubramanian in 1972, is extended, thus permitting the study of adsorption isotherms of the more usual kind (Langmuir, Frumkin, etc.) as well as other more complex types (e.g. multilayers, experimental isotherms…). Moreover, exact general equations in the form of faradaic instantaneous current vs. time and average current vs. potential (the polarographic curve) have been obtained. Nowadays computational techniques easily provide a numerical solution for these equations. The classical approximations proposed to obtain analytical expressions for these equations can be easily deduced from the general equations obtained in this paper, thus giving a general frame for these approximations. Their accuracy is also discussed.