铋掺杂二氧化钛纳米颗粒的制备及其可见光催化性能

采用水热法，以纳米管钛酸为前驱物制备了Bi掺杂的TiO₂，并利用X射线衍射、透射电子显微镜、X射线光电子能谱、紫外-可见漫反射光谱等手段对样品进行了表征. 以甲基橙的光催化降解为模型反应评价了样品的可见光催化性能. 结果表明，Bi离子并没有进入TiO₂的晶格中，而是以BiOCl的形式存在. 所制得的BiOCl/TiO₂复合物对甲基橙降解表现出较优越的可见光催化活性；当Bi/Ti摩尔比为1%，水热温度为130℃时，所制催化剂的光催化性能最佳，并对光催化活性提高的机理进行了讨论. 同时，该催化剂对4-氯苯酚降解也表现出较高的光催化性能.

Preparation of Bi-doped TiO2 nanoparticles and their visible light photocatalytic performance

Bi-doped TiO₂ photocatalysts were prepared by a hydrothermal method using nanotube titanic acid as the Ti precursor. The samples were characterized by X-ray diffraction, transmission electron microscopy, ultraviolet-visible diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. Methyl orange (MO) was used as a model contaminant to evaluate the visible light photocatalytic activity of the Bi-doped TiO₂ samples. We found that the Bi ions did not incorporate into the TiO₂ lattice but instead existed in the form of BiOCl. The obtained BiOCl-composited TiO₂ samples exhibited remarkable photocatalytic activity under visible light irradiation for the photodegradation of MO. The sample obtained when the Bi/Ti molar ratio was 1% and the hydrothermal treatment temperature was 130 ℃ (BTO-130-1) showed the highest photocatalytic activity. Moreover, a possible mechanism was proposed and the enhanced photocatalytic activity was discussed. The as-prepared catalyst also showed high photocatalytic activity for the photodegradation of 4- chlorophenol.