Ti^(3+)自掺杂的TiO_2(A)/TiO_2(R)/In_2O_3纳米异质结的制备与可见光催化性能

Preparation of Ti^(3+) Self-Doped TiO_2(A)/TiO_2(R)/In_2O_3 Nanoheterojunctions with Enhanced Visible-Light-Driven Photocatalytic Properties

以TiCl_3和InCl_3为Ti源和In源,在不使用还原剂的条件下,首先通过液相沉淀反应制备前驱体沉淀,然后采用后续水热处理制备Ti^(3+)自掺杂的TiO_2(A)/TiO_2(R)/In_2O_3纳米异质结,考察了水热处理温度对材料结构和性能的影响。利用X射线衍射、透射电子显微镜、X射线光电子能谱和紫外-可见漫反射光谱对样品进行表征。分别以罗丹明B和苯酚溶液为模拟废水评价了样品的可见光催化降解性能。结果表明,与纯的TiO_2、In2O_3以及Ti^(3+)自掺杂的TiO_2相比,Ti^(3+)自掺杂的TiO_2(A)/TiO_2(R)/In_2O_3纳米异质结在可见光区有明显的吸收,并具有良好的可见光催化降解性能,200℃下水热处理24h所得样品光催化降解罗丹明B的反应速率常数(0.0444min-1)分别是纯TiO_2和In_2O_3的17.76倍和8.71倍。瞬态光电流时间响应结果表明样品的光催化性能主要来源于TiO_2(A)/TiO_2(R)/In_2O_3纳米异质结导致的提高的光生电子和空穴分离效率。

Ti^3＋ self-doped TiO2（A）/TiO2（R）/In2O3 nanoheterojunctions were synthesized by hydrothermal treatment of the precursor obtained using TICL3 and InCL3 as the Ti and In source without the exist of reductant. The effects of hydrothermal treatment temperature on the properties of the samples were studied. The structure, crystallinity, morphology, chemical state and optical properties of the obtained samples were characterized by X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-Vis diffuse reflectance spectroscopy. Rhodamine B （RhB） and phenol solutions were used as simulated wastewater to evaluate the visible-light photocatalytic activity of the nanoheterojunctions. The Ti^3＋ self-doped TiO2 （A）/TiO2 （R）/In2O3 nanoheterojunctions exhibited extended visible light absorption and higher photocatalytic activity than that of pure TiO2, In2O3 and Ti^3 ＋ self-doped TiO2. The sample obtained after hydrothermal treatment at 200 ^ for 24 h exhibited the best visible light photocatalytic activity with a reaction rate constant of 0.044 4 min^-1, 17.76 and 8.71 times than that of pure TiO2 and In2O3. Photocurrent density results indicated that the improved visible-light photocatalytic properties which could be attributed to the enhanced photogenerated charge separation of the nanoheterojunction.