The synthesis of ZnTiO3/TiO2 composite photocatalysts and their photocatalytic performances

Abstract:

The ZnTiO3/TiO2 composite photocatalysts with high photocatalytic activity were synthesized by hydrothermal treatment of the [Ti4O9]2ˉ nanosheets after it was adjusted to a desired pH value with a 3 mol/L HCl solution and a 3 mol/L NaOH solution in the present of hexamethylenetetramine and Zn(NO3)2. The [Ti4O9]2ˉ nanosheets were prepared by using the layered tetratitanate K2Ti4O9 as the processor. First, the K2Ti4O9 sample was converted into a protonic tetratitanate H2Ti4O9 by exchanging K+ of K2Ti4O9. And then the H2Ti4O9 was mixed with the triethanolamine (TEAOH) to obtain the TEA+-intercalated tetratitanate compound. Finally, the TEA+-intercalated tetratitanate compound was dispersed in massive amounts of distilled water to obtain the [Ti4O9]2ˉ nanosheets. The structures and morphologies of the ZnTiO3/TiO2 composite photocatalysts were investigated by using X-ray diffraction (XRD) and scanning electron diffraction microscopy (SEM). Furthermore, the photocatalytic activities of the synthesized ZnTiO3/TiO2 composite photocatalysts were also characterized. The experimental results revealed that the ZnTiO3/TiO2 composite photocatalyst obtained at the value of pH = 7.0 exhibits the higher photocatalytic activity.

Key words:TiO2; Catalytic performance; Methylene blue; Degradation rate