Abstract: Coating carbon nanotube surface with TiO2 as anatase was performed by sol-gel method using Ti(OBu)4. The morphological structure of the photocatalyst particles was characterized by XRD and TEM. Absorbency was analyzed by the UV-Vis diffuse reflection spectra of TiO2 and CNT-TiO2 photocatalysts. The photocatalytic activities of the materials heat-treated at different reaction temperatures have been tested on decomposable substrate methyl orange solution under UV-light illumination. The results showed that the nanocomposites had excellent photocatalytic ability. When the wavelength was between 200 -800 nm, CNT-TiO2 nanocomposites had good absorbency. TEM micrographs showed that TiO2 was closely coated on the surface of carbon nanotubes. The best heat treatment temperature of CNT-TiO2 nanocomposites was 450 ℃. The crystal formof TiO2 was anatase and the diameter of crystal was 7.3 nm. The photodegradation rate of CNT-TiO2 nanocomposites was better than that of pure TiO2 under sunlight.

Key words: Sol-gel method, TiO2, CNTs, Photocatalysis