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纳米CeO2是一种性质独特的稀土氧化物,具有优异的催化活性、良好的热稳定性和化学稳定性以及电子、氧空位传递能力,常被用作贵金属催化剂的载体来提升材料的催化性能.贵金属-二氧化铈(M-CeO2)复合催化剂被广泛应用于CO催化氧化、水煤气转换、NOx还原以及固态氧化物燃料电池等领域,对治理环境污染和解决能源危机做出了重要贡献.CeO2与贵金属之间存在复杂的相互作用,这种相互作用对M-CeO2复合催化剂的催化性能有重要影响,而M-CeO2的结构类型与这种相互作用之间有着密切的关系,不同的结构类型会影响催化剂的稳定性、活性和选择性等.本文从M-CeO2复合催化剂的结构类型出发,以传统CeO2表面直接负载贵金属(M/CeO2)以及M@CeO2的核-壳结构、卵黄-壳结构、核-鞘结构和层状结构等类型作为对象,总结了贵金属与载体之间相互作用以及这种相互作用对催化剂性能的影响,分析了M/CeO2结构类型中CeO2形貌与催化活性之间的关系,归纳了不同类型M-CeO2催化剂的结构特点、合成方式以及在催化领域的应用表现,阐述了材料结构对催化活性的影响.这项工作将有利于合理地设计高效的M-CeO2复合型催化剂,实现经济高效的催化反应.
Nanocrystalline CeO2 is a unique rare earth oxide with excellent catalytic activity, good thermal and chemical stability, and electron and oxygen vacancy transport. It is often used as a carrier for noble metal catalysts to enhance the catalytic performance of materials. The noble metal-cerium oxide (M-CeO2) composite catalyst has been widely used in the fields of CO catalytic oxidation, water gas conversion, NOx reduction and solid oxide fuel cells, and has made important contributions to the control of environmental pollution and energy crisis. There is a complex interaction between noble metals. This interaction has an important influence on the catalytic performance of the M-CeO2 composite catalyst. The structural type of M-CeO2 is closely related to this interaction. Different types of structures Influence on the stability, activity and selectivity of the catalyst.In this paper, based on the structure type of M-CeO2 composite catalyst, the traditional CeO2 surface is directly loaded with the noble metal (M / CeO2) and the core-shell structure of M @ CeO2, , Core-sheath structure and lamellar structure as the object, summarizes the interaction between the precious metal and the support and the interaction of the catalyst on the performance The relationship between the morphology and the catalytic activity of CeO2 in the M / CeO2 structure type was analyzed. The structural characteristics, the synthesis methods and the application in the catalytic field of different types of M-CeO2 catalysts were summarized. The effects of the material structure on the catalytic activity This work will facilitate the rational design of efficient M-CeO2 composite catalysts for cost-effective catalytic reactions.