Dark desorption experiments

Impedance spectroscopy and electrochemical dye desorption experiments have been employed [339] to study the electrical characteristics of Ti02 nanocrystalline films in the dark. This study and the others cited above demonstrate how the conductivity changes (as a result of electron injection from the support electrode) can cause the porous/nanocrystalline layer to manifest itself electrically, such that the active region moves away (i.e., outward) from the support as the forward bias voltage is increased. The potential distribution has also been analyzed depending on whether the depletion layer width exceeds or is smaller than the typical dimension of the structural units in the nanocrystalline network [338]. 

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