Preparation of nano-TiO₂ composite photocatalysts and their photocatalytic performances for hydrogen production

p-MWNT-TiO₂ and p-MWNT/ZnTPP-TiO₂ composite photocatalysts were prepared by a sol-gel method, and their physical properties were characterized by thermogravimetric analysis (TG), transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and ultraviolet visible diffuse reflectance spectrum (UV-Vis/DRS). The results indicate that the crystallization temperature of TiO₂ has been delayed and the phase change restrained because carbon nanotubes have been doped into TiO₂. Compared with pure TiO₂, the absorptions of the composite photocatalysts were red-shifted obviously. The photocatalytic performance for hydrogen production is in an order of p-MWNT/ZnTPP-TiO₂ ≤ p-MWNT-TiO₂ ≤ P25 ≤ TiO₂.