Bi2Ti2O7/TiO2复合纤维：原位水热合成及光催化性能

采用静电纺丝技术制备的TiO2纤维作为模板和反应物,通过原位水热合成了具有异质结构的Bi2Ti2O7/TiO2复合纤维。利用X射线衍射(XRD)、扫描电镜(SEM)、能量散射光谱(EDS)、高分辨透射电镜(HRTEM)和紫外可见吸收光谱(UV-Vis)等分析测试手段对样品的结构和形貌进行表征。以罗丹明B为模拟有机污染物进行光催化降解实验。结果表明:花状Bi2Ti2O7纳米结构均匀地生长在TiO2纤维上,制备了Bi2Ti2O7与TiO2相复合的光催化材料,其光谱响应范围拓宽至可见光区,与纯TiO2纤维相比可见光催化活性显著提高,且易于分离、回收和循环使用。初步探讨了Bi2Ti2O7/TiO2异质结的生长机制和光催化活性提高机理。

Bi2Ti2O7/TiO2 Composite Fibers: In-situ Hydrothermal Synthesis and Enhanced Photocatalytic Properties

Heterostructured Bi₂Ti₂O₇/TiO₂ composite fibers were fabricated by in situ hydrothermal technique employing TiO₂ fibers as both template and reactant. The morphology and structure of Bi₂Ti₂O₇/TiO₂ composite fibers were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), energy-dispersive spectrometry (EDS), high-resolution transmission electron microscopy (HRTEM) and UV-Vis spectrocopy. The as-fabricated heterostructure composites are composed of flower-like Bi₂Ti₂O₇ assembled uniformly on the surface of TiO₂ fibers. The UV-Vis analysis indicates that the absorption spectrum of the sample is extended to the visible light region. Compared with the pure TiO₂ fibers, Bi₂Ti₂O₇/TiO₂ composite fibers exhibite enhanced photocatalytic activity in the decomposition of Rhodamine B (RB) under visible light. This material also shows good catalytic stability and is easy to be separated, removed from the system after reaction and cycles. Finally, the growth mechanism of Bi₂Ti₂O₇/TiO₂ heterojunction and the mechanism for the enhancement of photocatalytic activity of heterostructured composite fibers are discussed.