TiO2 Nanotube Films Prepared by Anodization in Glycerol Solutions for Photocathodic Protection of Stainless Steel

TiO2 nanotube array films were prepared on titanium foils by anodic oxidation in aqueous glycerol solutions with NH4F. The morphologies and properties of the films prepared in the solutions with different water contents were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-vis spectroscopy. The photocathodic protection effect of the films were evaluated by measuring the time evolution of the potential of 403 stainless steel coupled to the film photoanodes. The results showed that the TiO2 nanotube film prepared in the solution with 40 vol% water exhibited excellent photoelectrochemical properties. When the 403 stainless steel in a 0.5 M NaCl solution was coupled to the film under illumination, its potential decreased by 400 mV, showing that the TiO2 nanotube film provided effective photocathodic protection effect on the steel. Furthermore, the photoelectrochemical performance of the TiO2 nanotube film could be further improved by a TiCl4 solution treatment. (C) 2014 The Electrochemical Society. All rights reserved.