Heat treated titanate nanotube is based on the hydrothermally synthesized titanate nanowire having an average diameter of 50-100 nm and length upto 1-10 micron depends on the preparation parameters. Heat treated nanostructure is obtained by thermal annealing at 600 °C for 24 hours. During the thermal treatment the raw ionic trititanate structure going through a recrystallization process to anatase TiO2.
The transformation from trititanate to anatase is complete as shown in TEM images (fig. 1.). The formed anatase crystal structure is shown on fig. 2. (green line).
Fig. 1. Typical TEM image of TiO2-NW
Our technology has enable TiO2-NW product thermally treated at different temperatures. Fig. 2. shows XRD patterns of thermaly treated TiONW at different temperature. The dominant structure is anatase int he range of 600-850 °C and rutile at 900 °C.
Fig. 2. XRD patterns of titanate nanowires heat treated at different temperatures
The wire-like structure are remained even at temperature higher than 600 °C. TEM and SEM images of nanowires thermally treated at 800 °C shows the presence of remained TiO2-NW nanowires (Fig. 3.).
Fig. 3. Typical TEM (left) and SEM (right) images of TiO2-NW product annealed at 800 °C