Filling of TiO2 nanotubes by self-doping and electrodeposition

A highly efficient approach for metal filling of TiO2 nanotube layers is demonstrated. Electrochemical self-doping is used to switch selectively the bottom of TiO2 nanotubes into a conductive state. Subsequent metal electrodeposition therefore starts at the tube bottom and continues in a homogenous and controllable manner up the tubes. The approach essentially allows to deposit all material classes into TiO2 nanotubes and therefore provides the basis for a large variety of functional TiO2 nanotubes - composite materials.