γ-Fe2O3/Ag/TiO2的制备与抗菌性能

采用两步法合成了γ-Fe₂O₃/Ag/TiO₂复合光催化剂, 以大肠埃希氏菌(E. coli)为目标菌, 对数去除率为评价指标评价了催化剂的抗菌性能, 优化了催化剂的最佳制备参数. 通过X射线衍射、 扫描电子显微镜、 X射线光电子能谱和紫外-可见漫反射光谱等手段对催化剂进行了表征. 结果表明, 当Ti/Ag摩尔比为1:0.05, 煅烧时间为3 h, 煅烧温度为350 ℃时, γ-Fe₂O₃/Ag/TiO₂表现出最佳抗菌活性. 复合催化剂具有介孔结构, 比表面积为89.1 m²/g; 光吸收边界达690 nm, 有良好的可见光响应能力; 磁性较强, 在水处理应用中可有效分离和重复使用. 反应条件不受光源限制, 在有/无光照下均具有良好的抗菌活性, 且太阳光辐照下对E. coli的对数去除率可达6.28.

Synthesis and Antibacterial Performance of γ-Fe2O3/Ag/TiO2?

The photocatalyst γ-Fe₂O₃/Ag/TiO₂ with highly visible-light response was synthesized by two-step process. The photocatalytic antibacterial performance under visible light was evaluated by the lgReduction on the E. coli. The physical and chemical properties of γ-Fe₂O₃/Ag/TiO₂ were analyzed by means of X-ray powder diffraction(XRD), scanning electron microscopy(SEM), X-ray photoelectron spectroscopy(XPS), magnetic property measurement system(MPMS) and other characterization methods. The results indicate that the catalyst has mesoporous structure with a specific surface area of 89.1 m²/g and its absorption boundary reaches 690 nm. The catalyst exhibited excellent visible light response, remarkable antibacterial properties and strong magnetic properties, which can be effectively separated and reused in the water treatment. The optimal preparation parameters, such as the calcination temperature, the calcination time and n(Ti)/n(Ag) were determined as 350 ℃, 3 h and 1:0.05, respectively.