Abstract:

A spongelike nanostructured titanium dioxide (TiO2) film was fabricated on a titanium substrate by electrochemical anodic oxidation. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) experiments were performed to characterize the morphology and crystalline phase of the spongelike nanostructured TiO2 films. The effect of anodizing time on the thickness of the layers was examined. The relationship between the thickness of the spongelike nanostructured TiO2 film and its photocatalytic activity was investigated by the degradation of methyl orange solution. Results showed that the spongelike nanostructured TiO2 film had a high photocatalytic activity. The photocatalytic degradation rate of a methyl orange solution increased with the film thickness. The photocatalytic degradation rate by the spongelike nanostructured TiO2 film with a thickness of 2.2 μm was 6.4 times as large as that by the spongelike nanostructured TiO2 filmwith a thickness of 480 nm.

Key words: Anodic oxidation, Photocatalytic activity, Spongelike nanostructured TiO2 film