Electron transfer processes at the semiconductor-electrolyte interface

Electron transfer across the interface is a key step in the conduction of current through the junction of electronically conducting solids and ionically conducting liquids. Metals have a large density of electronic states that change from being full to being empty within a few kT of the Fermi energy so that there can be a continuous exchange of electrons between the metal and electronic states associated with the electrolyte. A change in potential between the metal and the electrolyte increases the transfer rate in one direction and decreases it in the other direction thereby changing the net current.