Ag修饰的Fe_3O_4/TiO_2复合磁性纳米纤维的制备及光催化性能

通过静电纺丝法制备了含有Fe3O4纳米粒子的TiO2纳米纤维,采用水热法对该纤维表面进行纳米Ag修饰,制备出具有较强磁性和较好光催化性能的复合纤维.采用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和紫外-可见光谱(UV-Vis)等对样品的结构和形貌进行表征,并以罗丹明B(Rh B)水溶液降解为模型反应,考察样品在紫外光照射下的光催化性能.结果表明,所制备的TiO2为锐钛矿结构,Fe3O4纳米粒子均匀分布在TiO2纤维中,Ag纳米颗粒比较均匀地分散在磁性TiO2纤维表面.经过纳米Ag修饰后,材料的光吸收能力大为增强,吸收带红移并扩展到可见光区.在紫外光照射40 min后,合成样品对Rh B的降解率达到99.5%.此外,Fe3O4纳米粒子的存在使该材料具有较强的磁性,可通过外加磁场将其分离回收.

Preparation and Photocatalytic Efficiency of Fe3O4/TiO2 Nanocomposite Fibers Modified with Ag Nanoparticles

Fe3O4/TiO2 nanofibers were prepared via electrospinning technique. Then, the samples were modified with Ag nanoparticles by hydrothermal method to obtain the composite fibers with strong magnetism and excellent photocatalytic efficiency. XRD, SEM, TEM and UV-Vis adsorption spectra were used to characterize and analyze the structure and morphology. The photocatalytic efficiency was tested under ultraviolet light irradiation using Rh B degradation as the model reaction. The results showed that TiO2 in all samples were anatases and Ag nanoparticles were scattered on the magnetic TiO2 fiber surface averagely. The UV-Vis spectra showed that TiO2 photoadsoption ability enhanced and the adsorption range were shifted to the visible light region. After modification with Ag nanoparticles, the photocatalytic efficiency of Rh B degradation rate can reach 99.5% under 40 min UV light irradiation. The new material with strong magnetism can be separated easily and cyclically used by adding the magnetic field.