We present a model that describes facilitated transfer of two cations across liquid|liquid interfaces in presence of a neutral weak acid and its conjugate base. The non‐trivial calculation of the initial equilibrium state is included, since it determines which processes are observed during voltammetry. In certain experimental conditions, the ion transfer reactions involve an interfacial cation exchange. The mechanism that takes place can be identified by measuring the peak‐to‐peak potential difference and the dependence of transfer potential with pH. We also derive a set of equations that allow to locate each experimental condition within a pH‐potential diagram that describes the system at a glance, according to the hydrophobicity of the ligand. Our results can explain potentiometric slopes obtained with ion‐selective electrodes and charge transfer processes with apparent super‐Nernstian responses.

The Cover Feature shows the interfacial cation exchange reaction facilitated by the presence of a neutral ligand in the non‐aqueous phase. In addition, the proton transfer facilitated by the interfacially formed complex is included. Special emphasis is placed on the environment of the processes responsible for electrochemical signals. More information can be found in the Research Article by T. A. Hernández et al.