ZnFe_2O_4/聚苯胺复合材料的制备及光催化性能

Preparation and photocatalytic properties of ZnFe_2O_4/polyaniline composites

采用化学氧化聚合法制备了组分含量比不同的ZnFe_2O_4/聚苯胺纳米复合材料(ZnFe_2O_4/PANI),对产物进行了表征,并研究了其对罗丹明B的吸附性能和可见光下的光催化性能.结果表明:随着纳米ZnFe_2O_4与苯胺的投料质量比(wZ/A)的减小,ZnFe_2O_4/PANI中聚苯胺(PANI)的质量分数和酸掺杂度均增大,复合物的可见光吸收性能和导电性均增强;同时,PANI的修饰提高了催化剂对罗丹明B的吸附能力,平衡吸附量随着wZ/A的减小而缓慢增加;产物的光催化性能先增加、后减小,wZ/A=10%的产物的光催化性能最好,且在重复使用5次内呈现良好的催化稳定性,可磁回收.结合活性物种捕获实验结果,推测其光催化反应过程中氧化性自由基和空穴共同参与了罗丹明B的降解.

Zinc ferrite/polyaniline composites （ZnFe2O4/PANI） with different mass ratios were prepared via chemically oxidative polymerization method. The composites were then characterized and their adsorption performance and the visible light photocatalytic activity were evaluated by using Rhodamine B （ RhB ） as the model organic pollutant. The results showed that the composites had an enlarged mass percent of PANI with gradually increased HCl doping degree, improved conductivity and absorption capacity for visible light as the mass ratio of ZnFe2O4 to aniline （wZ/A） decreased. Meanwhile, modification of ZnFe2O4 with PANI promoted the adsorption of RhB on the catalyst. The equilibrium adsorption capacity for RhB was gently elevated with the decreasing wZ/A. However, the photocatalytic activity of ZnFe2O4/PANI initially increased and then decreased. The photocatalyst with wZ/A = 10% exhibited the best photocatalytic activity under visible light irradiation, excellent stability in five cycles and good magnetic responsiveness for recollection. A possible photocat- alytic mechanism was proposed according to the trapping experiment of active spices.