Optimized synthesis for improved TiO2 NT array surface

Abstract

Different thicknesses of photoresist layers were deposited on the Ti foil in order to decrease the initial current during the anodization process, avoiding or diminishing in this way the formation of the initial compact TiO2 layer. The studies of the initial synthesis stages were performed in both cases, for the conventional synthesis and for that with photoresist layer on top of the Ti foil. TiO2 nanotube pH electrodes were fabricated to study the effect of this change in the anodization process. The nanostructure morphology was analyzed through scanning electron microscopy technique. Total removal of the undesirable layer and a complete release of the nanotube mouth were obtained. The pH electrodes were characterized utilizing a buffer solution and improved pH sensitivity and absence of hysteresis effects were observed for the devices fabricated with TiO2 nanotubes obtained with the optimized process.