Enhancement of Photocatalytic Activity of Mesporous TiO 2 Powders by Hydrothermal Surface Fluorination Treatment

Mesporous surface-fluorinated TiO2 (F−TiO2) powders of anatase phase with high photocatalytic activity are prepared by a one-step hydrothermal strategy in a NH4HF2−H2O−C2H5OH mixed solution with tetrabutylorthotitanate (Ti(OC4H9)4, TBOT) as precursor. The prepared samples are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, N2 adsorption−desorption isotherms, UV−vis absorption spectroscopy, and transmission electron microscopy. The production of hydroxyl radicals (•OH) on the surface of UV-illuminated TiO2 is detected by a photoluminescence (PL) technique with use of terephthalic acid as a probe molecule. The photocatalytic activity is evaluated by photocatalytic oxidation decomposition of…