Transition layer model of the oxide–electrolyte interface

A model of the oxide–electrolyte interface is proposed which accounts both for the Nernstian behaviour of the oxide (glass) electrode and the anomalous capacitance values of some oxides defined in terms of the change in surface charge with pH. The essential feature of the model is the existence of a transition layer of atomic dimensions in thickness within which is established an equilibrium between oxide and aqueous ionic species. The Nernstian behaviour of the oxide (glass) electrode is independent of the model chosen for the oxide–electrolyte double layer but requires that the oxide be conducting; the capacitance of the system, of course, is dependent on the detailed structure of the interface.