Semiconductors and Mott-Schottky Plots

Abstract

When a conductive electrode (e.g., metallic or glassy carbon) is in contact with an electrolytic solution, the excess electronic charge is accumulated at the electrode surface and charge distribution occurs in the solution only. This is related to the fact that as the number of charged species increases, the space in which the redistribution of charges occurs shrinks. At a metallic electrode–solution interface, the charge redistribution in solution depends on the applied potential and is described by the Guy-Chapman-Stern theory. The characteristic thickness of the diffuse layer in nonadsorbing electrolytes varies from 0.3 nm in 1 M to 3 nm in 0.01 M aqueous electrolyte, while the thickness of the Helmholtz layer is much smaller [17].