The structure of copper species, dispersed on nanostructured ceria (particles, rods and cubes), was analyzed by scanning transmission electron microscopy (STEM) and X-ray photoelectron spectroscopy (XPS). It was interestingly found that the density of surface oxygen vacancies (or defect sites), induced by the shape of ceria, determined the geometrical structure and the chemical state of copper species. Atomically dispersed species and monolayers containing few to tens of atoms were formed on ceria particles and rods owing to the enriched anchoring sites, but copper clusters/particles co-existed, together with the highly dispersed atoms and monolayers, on cubic ceria. The atomically dispersed copper sites and monolayers interacted strongly with ceria, involving a remarkable charge transfer from copper to ceria at their interfaces. The activity for the low-temperature water-gas shift reaction of the Cu/CeO₂ catalysts was associated with the fraction of the positively-charged copper atoms, demonstrating that the active sites could be tuned by dispersing Cu species on shape-controlled ceria particles.

通过扫描透射电子显微镜（STEM）和X射线光电子能谱（XPS）分析了分散在纳米结构二氧化铈（颗粒，棒和立方体）上的铜物质的结构。有趣的是，发现由二氧化铈形状引起的表面氧空位（或缺陷部位）的密度决定了铜物种的几何结构和化学状态。由于富集的锚固位点，在二氧化铈颗粒和棒上形成了原子分散的物种和含有很少至数十个原子的单分子层，但立方簇氧化铈上的铜簇/粒子与高度分散的原子和单分子层共存。原子上分散的铜位点和单分子层与二氧化铈强烈相互作用，涉及在界面处从铜到二氧化铈的显着电荷转移。_2种催化剂与带正电的铜原子的比例有关，表明可以通过将Cu物种分散在形状受控的二氧化铈颗粒上来调节活性位。