三维磁性复合材料ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO@Ag的制备及高效光催化降解罗丹明B的研究

Preparation of Three-dimensional Magnetic Composite ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO@Ag and Efficient Photocatalytic Degradation of Rhodamine B

光催化降解有机染料被认为是目前解决染料污染问题的一种理想策略。首先以三聚氰胺、氧化石墨烯(GO)和中空ZnFe_(2)O_(4)为前驱体通过热处理来构建3D结构ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO骨架;然后将银(Ag)作为助催化剂固定在ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO骨架上,制备了3D结构ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO@Ag复合光催化剂。并采用傅里叶变换红外(FT-IR)、X射线衍射(XRD)和扫描电子显微镜(SEM)等手段对材料的结构、形貌与化学组成进行了表征。结果表明,ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO@Ag复合催化剂在可见光的照射下对罗丹明B(RhB)的降解活性显著增强,在可见光照射下20 min内对RhB的降解率达到了97%,是ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO降解率的2倍。另外,ZnFe_(2)O_(4)的引入使得ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO@Ag复合材料具有良好的磁性,在外部磁场的作用下可以很容易地从反应体系中分离回收,重复使用5次后,光催化活性没有明显降低,表明该催化材料具有良好的稳定性和重复使用性能。

Photocatalytic degradation of organic dyes is considered as an ideal strategy to solve the dye pollution problem.In this study,melamine,graphene oxide(GO),and hollow ZnFe_(2)O_(4)were used as precursors to construct a 3 D ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO skeleton by heat treatment.Then,the silver(Ag)as a co-catalyst was immobilized on the ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO skeleton to prepare the 3 D ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO@Ag composite photocatalyst.The structure,morphology,and chemical composition of the obtained materials were characterized with Fourier transform infrared(FT-IR),X-ray diffraction patterns(XRD)and scanning electron microscopy(SEM).The experimental results showed that the degradation activity of ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO@Ag composite catalyst for Rhodamine B(RhB)was significantly enhanced,and the degradation rate of RhB reached 97%within 20 min under visible light irradiation,which was twice as high as that of ZnFe_(2)O_(4)/g-C_(3)N_(4)/rGO.In addition,the introduction of ZnFe_(2)O_(4)endowed the ZnFe_(2)O_(4)@g-C_(3)N_(4)/GO@Ag composite with good magnetic properties,which can be easily separated from the reaction system under the action of an external magnetic field.After repeated use for 5 times,the photocatalytic activity did not decrease significantly,indicating that the catalytic material has excellent stability and recyclability.