Self-Organized Titanium Oxide Nanotubes Prepared in Phosphate Electrolytes: Effect of Voltage and Fluorine Concentration

TiO2 a nanotube array was prepared using an anodization process. The process proceeded in a two-electrode cell containing of platinum sheet as the cathode electrode. Two phosphate-base electrolyte solutions containing different amounts of HF and NH4F were prepared. Different concentration of fluorine ions were examined in respected electrolytes. Current transient techniques were used to produce the TiO2 nanotubes at constant voltage of 18- 25V. It was revealed that anodization at 18- 22V, in so-called electrolytes would end up to nano-tubular structure. However the tubular structure prepared at 20V and from phosphate electrolyte containing of 0.5 wt% NH4F as well as 0.5 wt% HF, was recognized the best. The results were also confirmed by Scanning Electron Microscopy (SEM) images. Phase characterization of the nanotube oxide layer was carried out using x-ray diffraction (XRD) method.