Investigation on the TiO2 nanotubes ordering fabricated by anodizing on different substrate surface morphologies

In this article, TiO2 nanotubes fabricated on three titanium foils with different surface morphologies are investigated. Nanotubes anodized on titanium foils with no polishing process (A sample), with electropolishing process (B sample) and with electropolishing process in ethanolic electrolyte (C sample). By electropolishing, the surface roughness decreases considerably. Also, by adding ethanol to the electropolish electrolyte, the surface roughness decreases more in comparison to previous one. By decreasing surface roughness, interesting results are observed: 1) nanotubes diameter size distribution becomes more uniform significantly, 2) ordering of nanotubes increases highly and 3) outer diameter of tubes decreases from 125nm to 92nm.