AGING EFFECTS IN DEFECT-DOPED SEMICONDUCTING ELECTRODES

Time-dependent effects observed in defect-doped semiconducting electrodes are shown to be due to electromigration of defects in the depletion layer to the semiconductor-electrolyte interface. A method of determining the defect profile from photocurrent measurements is presented and illustrated with data for “aged” TiO2. The experimental profile is compared to a model calculation of the time evolution of the defect profile. These results suggest that electromigration of donors in the depletion layer will occur for all semiconductors where the donors have relatively large diffusion constants (mainly interstitial as opposed to substitutional dopants). © 1979, The Electrochemical Society, Inc. All rights reserved.