Preparation and Photocatalytic Behaviors of Nanoporous Polyoxotungstate-Anatase TiO2 Composites

Nanoporous anatase TiO2 crystalline particles coupled with Keggin or Wells-Dawson unit, H3PW12040/TiO2 or H6P2W18O62/TiO2, were prepared at a low temperature (200 °C) using sol-gel method combined with hydrothermal treatment at programmed temperature. The as-prepared composites have uniform anatase phase, and they exhibit both micro and mesoporosities with pore sizes of 0.6 and 4.0 nm, respectively, and their average size is lower than 10 nm. Photocatalytic tests show the composites exhibit relatively higher photocatalytic activities to decompose the organocholorine pesticide hexachlorobenzene(HCB) than anatase TiO2, the starting polyoxotungstates, and Eu2O3/TiO2 prepared by using sol-gel method, and this was attributed to (1) the synergistic effect of photoactive anatase TiO2 with the polyoxotungstate, and (2) the fascinating physical and chemical properties of the porous materials.