This work is intended to define an optimal methodology of preparation of highly ordered TiO2 nanotube arrays by a 60V anodization in a glycol ethylene solution. The effect of the presence of an initial superficial oxide on the sample, before operating the anodization growth, has been analysed. The best result has been obtained by a galvanostatic oxide growth on the titanium sheet, before the anodization process. The photoconversion efficiency was measured and we have obtained a maximum value of 12.97%, strictly in line with the literature. We have also underlined the necessity to operate a heat treatment using only dry atmosphere. (C) 2009 Elsevier Ltd. All rights reserved.