(Invited) Fabrication of High-Quality TiO2 Nanotubes on Conductive Glasses

In recent decades, titanium dioxide nanotube arrays has attracted many researcher’s interest due to their excellent physical and chemical properties, such as high order, large specific surface area, stability, and efficient electron transporting for dye-sensitized solar cells. However, it is difficult to prepare high quality TiO2 nanotubes on conductive glasses. Most TiO₂ nanotubes on conductive glasses reported in literatures exhibit poor organized structures.

As shown in Fig.1, a highly self-ordered titania nanotube arrays have been prepared on conductive glass (SnO₂:F) (FTO) substrates in ethylene glycol organic electrolyte which contains ammonium fluoride through anodic oxidation. The Ti film was deposited first on the FTO via DC magenetron sputtering. The sputtering power and substrate temperature were adjusted to obtain compact films. The incipient nanotubes have been covered by the surface oxide layer. To clean the surface, the sample after anodization was etched in diluted hydrofluoric acid solution via ultrasonic cleaning for a short time. Furthermore, the results indicate high quality TiO₂ nanotubes on the conductive glass substrates can be fabricated by using longer oxidation time (2h).