TiO_2/PANI/Fe_3O_4光催化磁流体的全流态合成及其光催化和磁回收性能

Synthesis of TiO_2/PANI/Fe_3O_4 photocatalytic magnetic fluid without drying process and its photocatalytic activity and magnetic recovery

以Fe_3O_4磁流体为磁核,经微乳液聚合包覆聚苯胺后制成催化剂载体,再采用低温水热法合成TiO_2并使其负载于载体表面,不经过烘干、研磨等步骤,在全程流态的情况下制备出具有复合结构的TiO_2/PANI/Fe_3O_4光催化磁流体。用X射线衍射仪(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、傅里叶红外分光光度计(FT-IR)、振动样品磁强计(VSM)对样品的物相组成、形貌、表面性质和磁学性质进行了表征。以苯酚为模拟污染物,评价其光催化活性;通过自制的磁回收装置,考察其磁回收特性。结果表明:在表面活性剂以及微乳液聚合法的作用下,合成反应过程中的团聚现象得到有效的抑制。在不经过烘干、研磨的条件下,制备出了颗粒均匀、催化活性和磁回收性能良好的TiO_2/PANI/Fe_3O_4光催化磁流体。不仅简化了合成的步骤,同时也避免了研磨等物理作用对催化剂结构的破坏,为光催化磁流体的合成提供了新的思路。

A composite magnetic photocatalytic titania（ photoactive shell）/polyaniline（ intermediate layer）/ferroferric oxide（ magnetic core） fluid was prepared by microemulsion polymerization and hydrothermal methods without the requirement for a drying or grinding process. The prepared composite particles were characterized by X-ray diffraction（ XRD）,transmission electron microscopy（ TEM）,scanning electron microscopy（ SEM）,Fourier transform infrared（ FT-IR） spectroscopy,and vibrating sample magnetometry（ VSM）. The photocatalytic activity of the magnetic fluid was evaluated in the photocatalytic degradation of phenol,and the magnetic recovery rate was studied using in-house recovery equipment. The results indicated that the photocatalytic activity and magnetic recovery of the TiO2/PANI/Fe3O4 photocatalytic magnetic fluid were acceptable,and that agglomeration was avoided using our microemulsion polymerization technique. This novel new method not only simplified the synthetic route to a photocatalytic magnetic fluid,but also avoided the damaging drying and grinding steps reported in previous preparations.