Charge transfer across the interface between two immiscible electrolyte solutions and analytical applications

Abstract

The transfer of several ions across the water/2-chloroethyl ether and water/o­dichlorobenzene interfaces has been investigated by DC and AC cyclic voltammetry. The standard Gibbs energies of ion transfer have been determined based on the tetraphenylarsonium tetraphenylborate assumption. The results have been compared with theoretical data calculated from an ionic solvation model. The transfer of transition metal-terpyridine complexes across the water/nitrobenzene interface has also been studied and from the voltammetric measurements the standard Gibbs energies of transfer have been evaluated. An amperometric detector based on membrane stabilized interface between two immiscible electrolyte solutions has been developed. It has been tested in a flow injection system for the determination of anions and cations. The detection limit of the detector has been determined to be about 5×10−7 M for the ions studied.