Fabrication and Photocatalytic Activity of TiO<sub>2</sub> Hollow Structures using One-pot Wet Chemical Process

Abstract

A facile one-pot wet chemical process to prepare pure anatase TiO2 hollow structures using ammonium hexafluorotitanate as a precursor is developed. By defining the formic acid ratio, we fabricate TiO2 hollow structures containing fluorine on the surface . The TiO2 hollow sphere is composed of an anatase phase containing fluorine by various analytical techniques . A possible formation mechanism for the obtained hollow samples by self -transformation and Ostwald ripening is proposed. The TiO2 hollow structures containing fluorine exhibits 1.2 - 2.7 times higher performance than their counterparts in photocatalytic activity . The enhanced photocatalytic activity of the TiO2 hollow structures is attributed to the combined effects of high crystallinity, specific surface area (62 ㎡g-1), and the advantage of surface fluorine ions (at 8%) having strong electron -withdrawing ability of the surface ≡ Ti-F groups reduces the recombination of photogenerated electrons and holes.