Synthesis of thin films of barium titanate and barium strontium titanate nanotubes on titanium substrates

In this study, well-ordered nanotubes of titania were fabricated by anodic oxidation of pure titanium foils in HF aqueous solution. Fe-SEM images indicate the average nanotubes diameter is ∼100 nm with a thickness of about 200 nm. Nanotube arrays of barium titanate and barium strontium titanate were synthesized under hydrothermal condition at 200 °C taking above-oxidized titania nanotubes as templates. In contrast to porous alumina membranes obtained by others using similar approaches, a different morphology was obtained in the current study. The nanotube arrays of barium titanate and barium strontium titanate may have many potential applications in microelectronics.