  Sol-gel electrophoresis is used to grow PbTiO3 nanotube arrays in porous
anodic alumina template channels, because it is a cheap and simple method for
the growth of nanostructures and has the advantage of better tube growth
control. Moreover, this method can produce nanotubes with high quality and more
condense structures. In this technique, semiconductor porous anodic alumina
templates are used to grow the nanotube arrays. Consequently, close-packed
PbTiO3 nanotube arrays are grown in the template channels. It is shown here
that, to the best of our knowledge, sol-gel electrophoresis is the only method,
applicable for producing PbTiO3 nanotubes with thickness below 20 nm (section
3.3). Also, the effect of deposition time on the wall thickness is
investigated, for a fix electrophoresis voltage. The thickness of the grown
nanotubes is uniform; an important issue for the ferroelectric properties of
the deposited nanolayers for future investigations.
