| Layered photocatalytic nanocomposite has received ever-increasing attention in field of photocatalytic science over recent years. The photocatalytic action of layered nanocomposite semiconductor is based on the charge rapidly transferring from guest to guest or from guest to host layer to decrease electron-hole recombination, so as to improve photocatalytic activity, and especially it can be recycled easily, this material has a potential applications in the area of environmental engineering.A series of layered titnate were synthesized by calcining the mixture of stoichiometric start materils. And then H0.8Fe0.8Ti1.2O/TiO2, H2La2Ti3O10/TiO2, Ho.8Nio.4Ti1.6O4/TiO2, H2La2Ti3O10/Fe2O3, H2La2Ti3O10/Fe2O3*, H2La2Ti3O10/MxOy (M=Fe, Cr, Cu, Mn, Co, Ni) nanocomposites with ultrafine particles highly dispersing in the interlayer were prepared by using sol-gel or hydrothermal synthesis method. These samples were charactered by TG-DTA, XRD, DRS, Specific surface area analysis, and Atomic absorption spectrometry analysis. Methyl orange used as a model dye was decomposed under irradiating of UV light and visible light. The results indicated Ho.gFe0.8Ti1.2O4/TiO2, H2La2Ti3O10/TiO2and Ho.gNio.4Ti1.6O4/TiO2 were capable of degrading methyl orange effectively. Particularly, under irradiation of visible light ( > 400nm), the decomposition ratio of methyl orange by using them as catalyst were superior to that of unsupported TiO2(P-25). The photocatalic activity of H2La2Ti3O10/MxOy(M=Fe, Cr, Cu, Mn, Co, Ni) were , more or less, higher than H2La2Ti3O10. It is notable that the photocatalytic activity of H2La2Ti3O10/Fe2O3 is almost the same as that of H2La2Ti3O10/Fe2O3* under irradiation with > 400nm although different methods are applied to fabricate them. In view of the simplicity, convenience and start materials obtained easily for hydrothermal synthesis, it is suggested that hydrothermal synthesis method is used to prepare layered nanocomposites more widely.
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