Growth of anodic TiO2 nanotubes in mixed electrolytes and novel method to extend nanotube diameter

摘要: ABSTRACT It is well known anodic TiO 2 nanotubes (ATNTs) can be obtained by the anodization of Ti foils in fluoride-containing solutions, and nanotube diameter proportional to applied voltages. However, growth kinetics ATNTs relationship between structural features anodizing parameters still remain unclear. Challenges always fabrication with large diameters due undesired breakdown event under high voltage NH 4 F solutions. Here, an interesting approach first proposed overcome these particular challenges. A series constant current processes fluoride-free H 3 PO solutions different concentrations (0.7 wt%, 0.5 wt% 0.2 wt%), mixed electrolytes containing both , have been compared detail. And we mainly focused on influence ratios outer correlation two types films. The results show that greatly increases amount a given concentration F. In contrast, length decreases increase experimental findings phenomenon elucidated theory electronic ionic rather than field-assisted dissolution.