Formation of double-walled titania nanotubes with cone like tips

摘要

Double-walled TiO2 nanotubes have been fabricated by electrochemical anodization of Ti foil in 0.3% ammonium fluoride solution in ethylene glycol with 2 vol.% of water at the low temperature of electrolyte and the subsequent annealing at 450 °C. The double-walled titania nanotubes structure with an upper honeycomb layer could be modified by sonication to the cone like tips.