Titania nanostructure arrays from lithographically defined templates

We report the fabrication of TiO2 nanostructures with lithographically defined templates. Interferomeric-lithography was used to define soft templates (polymer posts), and a sol-gel solution was deposited on a patterned surface. In the final step, calcination was employed to form uniform low aspect-ratio crystalline nonclose-packed TiO2 nanotube arrays over a large area. Similarly, nanotree arrays and parallel nanotunnels were prepared as well. The position and morphology of TiO2 nanostructures were well controlled. These TiO2 nanostructures have a potential technological importance in clean energy, biosensor, and drug release.