C@(Fe_3O_4-HNTS)-Ag/AgBr复合材料的合成与光催化性能研究

Preparation of composites C@(Fe_3O_4-HNTS)-Ag/AgBr and its photocatalytic properties

采用沉淀-光致还原法首次制备了复合光催化剂C@(Fe_3O_4-HNTS)-Ag/AgBr,通过SEM-EDS、XRD和UVVis对其形貌、物相结构、表面成分作了表征与分析.结果表明,含5%C@(Fe_3O_4-HNTS)的复合催化剂在紫外和可见光区域均有较强的光响应.在可见光(λ> 420 nm)照射下,采用C@(Fe_3O_4-HNTS)-Ag/AgBr做催化剂,历时20 min,水中甲基橙(MO)的降解率可达89. 72%.在反应体系中,·O_2^-和h^+是主要的活性物种,·OH是次要的活性基团. C@(Fe_3O_4-HNTS)表面的含碳物质和Fe_3O_4起了助催化剂的作用,二者的存在明显加快了MO的降解速率.复合光催化剂C@(Fe_3O_4-HNTS)-Ag/AgBr对染料具有较好的降解效果,可重复利用性好,具有潜在的应用价值.

The composite photocatalyst C@(Fe 3O 4-HNTS)-Ag/AgBr was prepared using precipitation-photoreduction method for the first time.The morphology,phase and surface composition of C@(Fe 3O 4-HNTS)-Ag/AgBr were characterized by SEM-EDS,XRD and UV-Visdiffuse reflectance spectra.The results show that the composite catalyst containing 5%of C@(Fe 3O 4-HNTS)has a strong light response both in UV and visible light regions.Under visible light(λ>420 nm)irradiation,C@(Fe 3O 4-HNTS)-Ag/AgBr was used as catalyst,which lasted 20 min,the degradation efficiency of MO was up to 89.72%.In the reaction system,·O-2 and h+are the main active species,and·OH is a secondary active group.The carbonaceous material and Fe 3O 4 on the surface of C@(Fe 3O 4-HNTS)played a catalytic role in the reaction system,which significantly accelerated the degradation rate of MO.The composite photocatalyst C@(Fe 3O 4-HNTS)-Ag/AgBr has a good effect on the degradation of dyes,and it has good repeatability and potential application value.