ABSTRACT
The authors begin this chapter addressing the actual measurement of both aspects of the response of a material film deposited on a current collector, employing as a reference experimental method the technique of cyclic voltammetry. The authors show how both kinetic and energetic aspects can be separately characterized, and address how to distinguish them in the experimental response. The authors discuss the observation of band tailing in energetically disordered semiconductors, as amorphous silicon, and then we review the capacitive properties of nanocrystalline titanium dioxide electrodes, used in mesoporous solar cells and photocatalysis. Since the voltage that can be extracted from a given material, in a solar cell configuration, is determined by the Fermi level separation, in these materials the tail states become the relevant ones for the production of photovoltage, rather than mobility edge energies.
