Skip to Main Content
Herein, we report on the influence of annealing temperature on the formation of anatase and rutile phase of TiO2. Electrochemical anodization was carried out in two electrodes bath consisting of excess Fluorine ions. The anode is a 0.1 mm thick Ti foil and the cathode is Pt electrode. Anodization was conducted at 20 V in 1M Na2SO4 electrolyte. The anodized foil was subjected to morphological and structural characterizations using field emission scanning electron microscope and Raman spectroscopy. As-anodized foil was found to be amorphous or weakly crystalline. When the oxide was heat treated, Raman spectroscopy analysis showed the diminishing of anatase peaks for samples annealed at 500 °C at Raman frequency 149.41 cm-1. This indicates that the transformation occurs at this range of temperatures with a more complete transformation at higher temperature. Annealing at higher than 600 °C the pattern shows a peak belonging to the rutile peak and it induces thickening of the nanotubes wall and at above 700 °C, the nanotubes structure has completely disappeared. For Rutile phase structural appeared at Raman frequency 633.59 cm-1 assigned as Raman vibrational mode Eg and A1g, respectively.