Abstract:

Chlorine-doped titanium pillared montmorillonite(Cl-TM) was prepared by the sol-gel technique in order to improve the photocatalytic activity. X-ray diffraction(XRD), scanning electron microscope(SEM), energy dispersive spectroscopy(EDS), UV-Vis diffuse reflectance spectroscopy(UV-Vis-DRS), photoluminescence spectrometer(PLS), X-ray photoelectron spectroscopy(XPS), fourier-transform infrared spectroscopy(FT-IR), N2 adsorption-desorption (BET) were used to characterize the products. The results show that the products had typical anatase phase while keeping the pillared structure of montmorillonite. The presence of montmorillonite can inhibite the phase transformation of titania from anatase to rutile. In addition, Chlorine-doped sample can reduce the band gap energy of TiO2 from 3.19 eV to 3.14 eV and therefore extend the light response of TiO2 to visible light region. XPS data imply that chlorine existed in the TiO2 crystal lattice as an anion. Furthermore, the photocatalytic degradation of PNA by Cl-TM indicates that the activity was significantly affected by chlorine-doped amount, and the optimized content is 6%(molar ratio of Cl to Ti).

Key words: chlorine-doped, titanium pillared montmorillonite, photocatalytic, p-nitroaniline