Lanthanum-substituted bismuth titanate nanotubes

Ferroelectric (Bi1−xLax)4Ti3O12 (BLT) nanotubes doped with 0.85 at% La were fabricated with the aim of developing an alternative to conventional technologies. A technique based on the wetting of a polymeric metal-organic source was used in the fabrication process for ferroelectric nanotubes. This technique involved the use of porous alumina produced by anodic aluminum oxidation as a template. It was demonstrated that these nanotubes can be used for the large-scale fabrication. X-ray diffraction measurements and transmission electron microscopy studies show that the crystal grains in the BLT nanotubes with a wall thickness of approximately 20 nm have a ferroelectric BLT phase with a random orientation and a grain diameter of 10 nm to 60 nm. Promising electrical properties of the BLT nanotubes for electronic devices could be confirmed in I–V measurements. The measured leakage current for a BLT nanotube with a length of approximately 2.5 μm at an applied voltage of 2 V was approximately 2.5×10–11 A.