School of Biological and Medical Engineering , Hefei University of Technology , Hefei 230009 , P. R. China.
CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics , University of Science and Technology of China , Hefei 230027 , P. R. China.
Langmuir. 2018 Apr 10;34(14):4298-4306. doi: 10.1021/acs.langmuir.8b00302. Epub 2018 Mar 26.
This work reports a novel FeO@polydopamine/Au/polydopamine core/shell nanocomposite toward a magnetically separable nanocatalyst. Because the polydopamine (PDA) layer-sandwiched Au nanocrystals were prepared by a layer-by-layer method, the content of Au could be controlled by varying the Au shell number (such as burger-like FeO@PDA/Au/PDA/Au/PDA). FeO@PDA/Au/PDA exhibited excellent catalytic activity in reducing p-nitrophenol because the substrate could penetrate the PDA shell. Owing to the protection of the PDA shell, FeO@PDA/Au/PDA presented higher cyclability than FeO@PDA/Au. The activity of FeO@PDA/Au/PDA maintained 95% after 7 cycles, while that of FeO@PDA/Au was only 61%. The detailed cycling catalytic mechanism was investigated, and it was found that the catalytic rate of FeO@PDA/Au/PDA/Au/PDA was faster than that of FeO@PDA/Au/PDA because of the higher Au content. Interestingly, this method could be extended for other magnetic nanocomposites with two different kinds of noble metal nanocrystals integrated within one particle, such as FeO@PDA/Au/PDA/Ag/PDA and FeO@PDA/Au/PDA/Pd/PDA.
这项工作报道了一种新型的 FeO@聚多巴胺/Au/聚多巴胺核/壳纳米复合材料，作为一种可通过磁场分离的纳米催化剂。由于聚多巴胺（PDA）层夹Au 纳米晶是通过层层方法制备的，因此通过改变 Au 壳的数量（如汉堡状的 FeO@PDA/Au/PDA/Au/PDA）可以控制 Au 的含量。FeO@PDA/Au/PDA 在还原对硝基苯酚方面表现出优异的催化活性，因为底物可以穿透 PDA 壳。由于 PDA 壳的保护，FeO@PDA/Au/PDA 比 FeO@PDA/Au 具有更高的循环稳定性。FeO@PDA/Au/PDA 在 7 次循环后保持 95%的活性，而 FeO@PDA/Au 仅为 61%。详细的循环催化机理研究表明，由于更高的 Au 含量，FeO@PDA/Au/PDA/Au/PDA 的催化速率比 FeO@PDA/Au/PDA 更快。有趣的是，这种方法可以扩展到其他具有两种不同贵金属纳米晶集成在一个颗粒内的磁性纳米复合材料，如 FeO@PDA/Au/PDA/Ag/PDA 和 FeO@PDA/Au/PDA/Pd/PDA。
