TiO2 nanotube layers: Flexible and electrically active flow-through membranes

In the present work we demonstrate the fabrication and use of a new generation of TiO2 nanotube membranes. We show that anodic oxide nanotube growth can be performed through a patterned Ti foil into an underlying Al metal layer. After the selective dissolution of the Al/alumina layer, a very well defined both side open suspended TiO2 nanotube layer can be obtained. Using lithographic patterning of the anodization area allows to achieve very large scale, flexible and well electrically connected nanotubular flow-through membranes with fast electrical switching features over the entire membrane.