Mechanistic formation of TiO2 nanotubes via anodisation – effect of operating voltage and time

Abstract

Titanium dioxide (TiO) nanotubes hold great potential for application in dye-sensitised solar cells for they provide a one-dimensional transport route for generated charge carriers. An investigation is launched into the formation of these structures during the anodisation of commercially pure titanium foil sheets in organic electrolyte solutions under varying experimental conditions. Important parameters that play a role during the formation of TiO nanotubes are the operating voltage and time. The present work shows that an increase in voltage results in an increase in the tube diameter and length, whereas an increase in tube length is observed with extended anodisation time periods. Based on these findings a mechanistic model is presented for the formation of the nanotubes under the experimental conditions presented