Solvothermal preparation of TiO2/montmorillonite and photocatalytic activity

Nanocomposite photocatalysts of titania pillared montmorillonite were prepared by solvothermal reaction using water and ethanol as solvent, hexamethylene tetramine as precipitant and titanium trichloride as precursor. Phase composition, particle morphology, specific surface area, element content etc. of these samples were characterized by using X-ray diffraction(XRD), transmission electron microscopy(TEM), nitrogen gas adsorption BET method (BET) and atomic absorption spectrophotometry (AAS). The composite photocatalysts had a mesoporous structure with the distribution of pore diameters centered at 6 to 10 nm, which obviously increased the specific surface area. The effect of different TiCl3-montmorillonite ratios on the photocatalytic activity by degrading methylene blue in aqueous solution was investigated. TiO2-montmorillonite with a mass ratio of 0.2:1 showed the highest photocatalytic activity because of its relatively large specific surface area and suitable pore size distribution.