Formation of 1-D nanostructures of titanate thin films and thermal stability study

One-dimensional (1-D) layered titanate nanotubes and nanoribbon thin films were prepared via the hydrothermal reaction of Ti metal flakes with concentrated NaOH solution. TEM, SEM, and XRD studies of the reaction products revealed that 20-nm-wide and about 1-microm-long nanoribbons formed in 5 M NaOH aqueous solution at 140 degrees C for 12 h, while 6 aproximately 8-nm-wide and several hundred-nanometer-long nanotubes formed with 10 M NaOH. The effect of post treatments on the thermal stablity, phase structure and morphology of the as-prepared nanotubes films was investigated. Different morphologies and crystallinity changes of the as-prepared nanotubes films during heat treatment process are attributed to the sodium impurity.