Photoelectrochemical properties of self-organized TiO(2) nanotubes formed by electrochemical anodization of titanium sheets and their working mechanism are investigated. Formation and growth of self-organized nanotubes were carried out by Titanium anodization in acid electrolyte containing fluorides. Annealing of the samples was performed in order to increase the crystallinity of the material. Also some results obtained with samples annealed in Nitrogen atmosphere are presented. Electrochemical Impedance Spectroscopy was used to give an interpretation of the main charge transfer processes that occur at the nanotube/electrolyte interphase. The use of glycerol as hole scavenger was considered in order to improve the photoelectrochemical performance of the samples. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.