Synthesis and Characterization of Thermally Stable Nanotubular TiO2 and Its Photocatalytic Activity

Hydrogen titanate nanotubes obtained by hydrothermal synthesis are treated with sol containing titanium. The products are characterized with transmission electron microscopy, X-ray diffraction, thermal gravimetric analysis, and Raman spectroscopy. Their photocatalytic performance is evaluated by the photocatalytic degradation rates of methyl orange in aqueous solution under UV-vis light irradiation. The results reveal that the treated nanotubes are more thermally stable and exhibit better photocatalytic performance than primary nanotubes. The treated nanotubes can keep a tubular structure when calcined at 400 degrees C. However, their precursors collapse when they are calcined only at 300 degrees C. The more thermally stable new functional TiO2 nanotubes can be prepared by using sol containing other elements instead of sol containing Ti in the future.