A series of ceria‐supported Rh nanoparticles (NPs) that have various particle sizes of 2–7 nm was prepared to investigate the size effect of Rh NPs on NO reduction in NO–CO–C₃H₆–O₂ under stoichiometric conditions. The turnover frequency (TOF) for NO reduction on Rh NPs increased drastically according to their particle size. The strong size dependence of the TOF was attributed to the oxidation states of Rh NPs but not to particle geometries, which include fractions of surface local sites (e.g., corner, edge, plane) and the surface crystal structures (e.g., Rh(1 1 1), (1 0 0)). The variation of the TOF with the Rh metal fraction suggested that Rh metal ensembles are highly active species for NO reduction.

中文翻译：

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化学计量一氧化氮-一氧化碳-丙烯-氧反应中铑/二氧化铈还原铑/二氧化铈金属化合物的形成

制备了一系列具有2–7 nm各种粒径的铈土负载的Rh纳米颗粒（NPs），以研究化学计量比条件下Rh NPs对NO还原NO–CO–C ₃ H ₆ –O ₂的尺寸影响。Rh NP上NO还原的周转频率（TOF）根据其粒径而急剧增加。TOF的强尺寸依赖性归因于Rh NPs的氧化态，但不归因于颗粒几何形状，包括表面局部位点（例如，拐角，边缘，平面）和表面晶体结构（例如Rh（1 1 1），（1 0 0））。TOF随Rh金属分数的变化表明Rh金属团簇是用于还原NO的高活性物种。