3D electrodes for dye-sensitized solar cells: Synthesis of ITO nanowire arrays inside the TiO₂ nanotubes

In the present study, ITO nanowires electrode within the anodized TiO ₂ nanotubes without using the polycarbonate membrane templates were attempted. The process begins with an anodized TiO₂ nanotube arrays (TNA) and subsequent growth of indium-tin-oxide (ITO) nanowires into the TiO₂ annotube arrays via the electrophoretic process (EPD). The open-end of TiO₂ nanotubes were synthesized for the photoelectrode of DSSC. ITO nanowires were then grown into these TNAby EPD process. The composite of ITO/anodized TNA was employed as the working electrode for the assembly into DSSCs. The advantage of the present method is that the membrane templates in EPD process were not required. In addition, the ITO nanowires will surely not contact each other which might cause short circuit. The morphologies and the structures of ITO nanowires and TNA electrode were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM).