Formation of titania nanotube arrays by anodisation: DOE approach

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Self-organised TiO2 nanotubes were obtained on titanium by anodisation in Glycerol-H2O DI (50-50 v/v) electrolyte containing NH4F. A design of experiments (DOE) based on a 2(k) factorial design with four replicates at the center point was used in order to study the influence of voltage, anodisation time and fluoride concentration and their possible interactions on the obtainment of titania nanotubes. The statistical analysis showed that voltage is the only significant factor. The best condition according to the response surface analysis is the centre point (1%NH4F, 20 V, 2 h). Electrochemical tests performed in Ringer's solution showed that TiO2 nanotubes coated titanium is less corrosion resistant than as received titanium.