Charge transfer between two immiscible electrolyte solutions Part II. The investigation of Cs+ ion transfer across the nitrobenzene/water interface by cyclic voltammetry with IR drop compensation

Abstract

The transfer of Cs + ion across the interface of two immiscible electrolyte solutions, 0.05 M LiCl in water and 0.05 M tetrabutylammonium tetraphenylborate in nitrobenzene, was investigated by cyclic voltammetry with four-electrode system. The positive feedback was used for the elimination of the ohmic potential drop between the tips of the Luggin capillaries. The standard potential differences for Cs + and tetrabutylammonium cations and for tetraphenyl-borate anion, which were deduced from the present experimental results, are in very good agreement with those calculated from the extraction data. The value of the diffusion coefficient of Cs + ion in water D Cs +(w)=2.4×10 −5 cm 2 s −1 was estimated. The kinetics of Cs + ion transfer across the nitrobenzene/water interface is characterized by the apparent rate constant k app ø =5.5×10 −2 cm s −1 and by the formal charge transfer coefficient α=0.46.