Controllable Synthesis and Photocatalytic Activity of Anatase TiO2 Single Crystals with Exposed {110} Facets

Abstract

Anatase TiO 2 single crystals with a high percentage of the high surface energy {110} facets have been successfully synthesized in a simple and economical way using a modified hydrothermal technique in the presence of hydrogen peroxide and hydrofluoric acid. The morphology and structure of the TiO 2 single crystals were characterized by X-ray diffraction, scanning electron microscopy, and Raman spectroscopy. The photocatalytic activity of the TiO 2 crystals for the degradation of methylene blue dye was investigated by ultraviolet light irradiation. The effects of the amounts of HF and H 2 O 2 on the morphology of TiO 2 have been studied. The reaction time and temperature have also been investigated. In the TiO 2 single crystals, the {001} and {110} facets are present at the same time. The results indicated that a high yield of single crystals with exposed {110} and {110} facets could be obtained by adjusting the reaction time, reaction temperature, and amounts of HF and H 2 O 2 . The anatase TiO 2 single crystals with exposed {110} facets showed higher photocatalytic activities than those without. 采用水热法合成了同时具有最高表面能{\{}110{\}}和{\{}001{\}}晶面的锐钛矿 TiO 2 单晶, 通过 X 射线衍射、扫描电镜和激光拉曼光谱等手段对样品的形貌和结构进行了表征, 并系统考察了过氧化氢、氢氟酸和反应温度等关键因素对所得样品中{\{}110{\}}面比例的影响, 实现了持续提高{\{}110{\}}面比例的过程. 在光催化降解亚甲基蓝反应中, 具有{\{}110{\}}面的锐钛矿 TiO 2 单晶的光催化活性显著高于无{\{}110{\}}面的单晶. The controlled synthesis of a series of the anatase TiO 2 crystals with highly reactive {110} and {001} facets under the guidance of first-principle quantum chemical calculation are carried out in this work.