ZnFe₂O₄?Fe₂O₃/PANI复合材料的制备及可见光催化性能

Preparation and Visible-Light Photocatalytic Performance of ZnFe₂O₄?Fe₂O₃/PANI Composites

本文采用共沉淀法制备了铁酸锌–氧化铁复合纳米粒子(ZnFe2O4?Fe2O3),进一步采用紫外光辅助化学氧化聚合法使其与聚苯胺(PANI)复合,制备了复合光催化剂(ZnFe2O4?Fe2O3/PANI),借助X射线粉末衍射、红外光谱仪、紫外可见分光光度计、扫描电子显微镜、振动样品磁强计对产物进行表征,并研究了苯胺用量对产物的组成、吸收光谱、形貌和光催化性能的影响。结果表明,随苯胺用量的增大,复合物的形貌呈现由小颗粒向大颗粒、至纳米纤维的变化,样品中的PANI含量增大,催化剂对可见光的吸收性能和罗丹明B(RhB)的降解率均增强。经过120min可见光催化降解,催化剂对RhB的降解效率为75.5%。铁磁性和良好的磁响应性使得ZnFe2O4?Fe2O3/PANI可以被磁铁回收和再利用,在重复使用四次的催化剂对RhB的降解率为64.4%。

The composite nanoparticle consisted of zinc ferrite and hematite (ZnFe2O4?Fe2O3) was prepared through a simple co-precipitation method. Then ZnFe2O4?Fe2O3 was modified with polyaniline (PANI) via UV-assisted chemical oxidation polymerization to fabricate the composite photocatalysts (ZnFe2O4?Fe2O3/PANI). And the products were characterized by X-ray diffraction, infrared spectroscopy, ultraviolet spectrometer, scanning electron microscopy and vibrating sample mag-netometer. Besides, the effect of the aniline amount on composition, absorption, morphology and photocatalytic efficiency of the composite photocatalysts was investigated. The results show that with the increase of the amounts of aniline in the synthetic process the composites present various morphologies including small nanoparticle, big granular nanoparticle, and nanofiber. At the same time, the mass content of PANI in the composite is enhanced, and the composite owns im- proved visible light-harvesting ability and photocatalytic activity under visible light irradiation. The degradation rate of rhodamine B (RhB) was up to 75.5% after 120 min. Ferromagnetism ma- kes ZnFe2O4?Fe2O3/PANI susceptible to magnetic field and easy to be collected magnetically for iterative use. 64.4% RhB was degraded when the photocatalyst was used after 4 times.