Chemistry Reference
In-Depth Information
1.4.2. Limitations ofthe Basic Theories
The kinetic theory described by the above equations is derived with several basic
assumptions:
962
1. Electron transfer occurs directly between the levels in the bands and the levels
in solution
2. The energies of electrons and holes in the band taking part in the charge trans-
fer are confined in a narrow interval (on the order of
kT
) of the band edge at
the surface.
3. The position of the band edge relative to the energy levels of the redox system
is independent of the potential change in the interface region, i.e., all the
applied potential drops across the space charge layer in the semiconductor.
