Electrochemical characteristics of TiO2 nanotubes with different diameters

In the present study we investigate the electrochemical characteristics of self-organized nanotubular TiO₂ layers prepared by anodization of pure Ti through different electrochemical methods. The nanotubular TiO₂ layers show n-type semiconductor property. Compared with the original pure Ti, the nanotubular TiO₂ layers have better electrochemical durability in the NaCl (0.9 wt.%) + NaCl (0.2% wt.%) solution (pH = 5.0) at room temperature. The variation of the nanotube diameter induced the changes of the Helmholtz double layer between the nanotubular layer and test solution, which influences their electrochemical characteristics.