Preparation of Fluorine-DopedTiO2Photocatalysts with Controlled Crystalline Structure

Abstract

Nanocrystalline F-dopedTiO2powders were prepared by sol-gel route. The thermal behavior of the powders was recorded by DTA/TG technique. The crystalline phase of the fluorinatedTiO2powders was determined by X-ray diffraction technique. It was demonstrated that F-doping usingCF3COOH favors the formation of rutile along with anatase phase even at low temperature. Moreover, the rutile's phase content increases with the increase of the quantity of the fluorine precursor in the starting solution. The surface area of the powders and the pore size distribution were studied byN2adsorption-desorption using BET and BJH methods. X-ray photoelectron spectroscopy (XPS) revealed that the fluorine is presented in theTiO2powders mainly as metal fluoride in quantities∼16 at %. The F-dopedTiO2showed a red-shift absorption in UV-vis region which was attributed to the increased content of rutile phase in the powders. The powders exhibited enhanced photocatalytic activity in decomposition of acetone.