以水热法制备的CeO2纳米棒为载体，分别采用溶胶法和沉积法对其进行纳米金修饰，得到两种不同纳米金修饰方法制备的Au/CeO2复合物。在MV-Fenton体系中用紫外分光光度法对两种Au/CeO2复合物的抗氧化性能进行研究。结果表明：溶胶法制备的Au/CeO2（S-Au/CeO2）比沉积法制备的Au/CeO2（D-Au/CeO2）展现出更好的抗氧化性能。进一步研究表明：沉积法制备过程可能破坏了CeO2的表面结构，导致其抗氧化性能降低；另外，溶胶法负载的AuNPs和CeO2之间的电子传递也使其抗氧化性能增强。
The application of Au nanoparticles (AuNPs) modified CeO2(Au/CeO2) as an antioxidant has great potential in the field of life health, and exploring the antioxidant activities of Au/CeO2 prepared by different methods is helpful for optimizing the property of Au/CeO2. In this work, two different Au-modified CeO2 were synthesized by modifying AuNPs on the surface of CeO2 nanorods using sol-immobilized and deposition methods, respectively. The antioxidant activities of two different Au/CeO2 were studied by UV method in the MV-Fenton system, and the results showed that the antioxidant activity of Au/CeO2 by sol-immobilized method (S-Au/CeO2) was higher than that of Au/CeO2 by deposition method (D-Au/CeO2). The affecting factors on the differences between the antioxidant properties of the two Au/CeO2 were further investigated. We suppose that the surface structure of CeO2 may be damaged in the process of preparation by deposited method, which resulted in the lower antioxidant activity of D-Au/CeO2. In addition, the electron transfer between sol-immobilized AuNPs and CeO2 contributed to the higher antioxidant activity of S-Au/CeO2. These results have great significance for the functional preparation and antioxidant property regulation of Au/CeO2.
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