Fabrication of pure and Nb-TiO 2 nanotubes and their functional properties

TiO 2 and Nb-doped TiO 2 nanotubes were obtained on flexible polymeric substrates (Kapton HN) and alumina with high roughness (alumina substrate with granular surface). Nanotubes were prepared by electrochemical anodization of a Ti thick film. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to investigate the morphology of the structures and the roughness of the substrates. The functional properties of tubular arrays obtained on flexible and rough substrates were investigated towards two applications, namely, chemoresistive gas sensors and flexible dye sensitized solar cells. © 2011 Elsevier B.V. All rights reserved.