Highly ordered TiO2 nanotube-stumps with memristive response

In the present work, we produce highly ordered and defined short aspect ratio self-organized TiO2 nanotubes - so called titania nanotube stumps [TNS] - by anodizing Ti in a HF/H3PO4 electrolyte. These TNS-layers are ideal for a conformal filling by metal sputter deposition. After decorating amorphous TNS with a Pt top contact, we investigate the solid-state current-voltage behavior and find a strongly pronounced memristic behavior. We ascribe the finding to the high vacancy density present in TNS bottoms prepared under high ion flux conditions.