The Effect of Acid Treatment and Reactive Temperature on the Formation of TiO2 Nanotubes.

TiO2 nanotubes (TNTs) were synthesized by a hydrothermal method from commercial TiO2 in NaOH followed by HCl washing. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmitting electron microscopy (TEM), and Brunauer-Emmet-Teller (BET) measurements. The untreated acid samples (pH ~ 12) don't appear nanotubes structure, while acid-treated samples until the pH reached around 2 have approximate diameters of nanotubes of 10 nm. The samples reaction temperature at 135 °C appear nanotubes structure while the samples reaction temperature at 150 °C have combination of the nanotubes and the samples treatment temperature at 170 °C appear both nanotubes structure and particles clumping together. The surface area of the TNTs was 83,5 m2/g while the surface area of commercial TiO2 particles was 41 m2/g.