摘要
Metal-oxygen bonding of the Ce-doped LaCoO 3 system remains largely unexplored despite extensive studies on its magnetic properties. Here, we investigate the structure and local structure of nanoscale La 1−x Ce x CoO 3 , with x = 0, 0.2, and 0.4, using the Rietveld refinement and synchrotron X-ray absorption techniques, complemented by topological analysis of experimental electron density and electron energy distribution. The Rietveld refinement results show that LaCoO 3 subject to Ce addition is best interpretable by a model of cubic symmetry in contrast to the pristine LaCoO 3 , conventionally described by either a monoclinic model or a rhombohedral model. Ce 4+ /Co 2+ are more evidently compatible dopants than Ce 3+ for insertion into the main lattice. X-ray absorption data evidence the partially filled La 5d-band of the pristine LaCoO 3 in accordance with the presence of La–O bonds with the shared-type atomic interaction. With increasing x, the increased Ce spectroscopic valence and enhanced La–O ionic bonding are noticeable. Characterization of the local structures around Co species also provides evidence to support the findings of the Rietveld refinement analysis.