Tianli Liu,Jian Zhang,Ye Xiao,Yuting Xia,Mingjie Xu,Jingxi Zhang,Ruiping Liu,Chang-An Wang
Supported noble metal catalysts have a high catalytic activity and selectivity. However, fast surface reconstruction and sintering of noble metal particles during a high-temperature reaction process pose a major challenge to the stability of the catalysts. In this study, sinter-resistant supported noble metal catalysts were prepared by constructing an oxide nanotrap. Pt/Al2O3 was used as a research paradigm. Dopamine was applied as a structure-directing agent and pore-forming agent to form a porous CeO2 overlay on the surface of Pt/Al2O3 and encapsulate Pt nanoparticles. Due to the confinement of CeO2 and its interaction with Pt, the modified Pt/Al2O3@CeO2 exhibits superior catalytic activity and antisintering stability. This method can be extended to other supported catalyst systems.
Encapsulation of small noble metal nanoparticles has received attention owing to the resulting highly increased stability and high catalytic activity and selectivity. Among the types of inert metal oxides, CeO 2 is unique. It is inexpensive and highly stable, and, more importantly, the unique electronic configuration gives it a strong capability to provide active oxygen. The method of fabricating CeO 2 -encapsulated noble metal nanocatalysts is determined by the requirements of the application. In this review, we first describe the various types of encapsulated noble metals and then the current developments of synthesis in detail, including the types of hybrid nanostructures and successful synthetic strategies. The following section, concerning catalytic applications, is divided into three topics: anti-sintering capabilities, catalytic activities and selectivities. We hope that this review of the recent achievements and the proposed strategy for addressing the emerging challenges will inspire further developments in this research area.
危险品化学品经营许可证（带存储）