具有{110}面的锐钛矿TiO_2单晶的可控合成与光催化性能

Controllable Synthesis and Photocatalytic Activity of Anatase TiO_2 Single Crystals with Exposed {110} Facets

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TiO2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TiO2单晶的光催化活性显著高于无{110}面的单晶.

Anatase TiO2 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 TiO2 single crystals were characterized by X-ray diffraction,scanning electron microscopy,and Raman spectroscopy.The photocatalytic activity of the TiO2 crystals for the degradation of methylene blue dye was investigated by ultraviolet light irradiation.The effects of the amounts of HF and H2O2 on the morphology of TiO2 have been studied.The reaction time and temperature have also been investigated.In the TiO2 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 H2O2.The anatase TiO2 single crystals with exposed {110} facets showed higher photocatalytic activities than those without.