Abstract
The present paper summarizes recent progress on the formation of TiO2 nanotubes and briefly reports unique and enhanced properties of TiO2 related to the morphology. The morphology and thickness of TiO2 nanotube layers have been developed by tailoring electrochemical conditions, that is, tuning the tube growth rate and the dissolution rate. By suppressing pH variations (due to current fluctuations) lead to thicker TiO2 nanotubes with extremely smooth and homogeneous walls. Clearly the photoelectrochemical responses and contact angles on the nanotube layers are strongly altered by the presence of nanotubes compared to flat TiO2 surfaces.