Surface Stabilizes Ceria in Unexpected Stoichiometry

摘要: The prototype reducible oxide ceria is known for its rich phase diagram and ability to absorb deliver oxygen. high oxygen storage capacity the basis use of in catalytic sensor applications where surface plays a paramount role device functionality. By direct imaging, we reveal reconstruction (111) five periodic structures representing reduction stages ranging from CeO2 Ce2O3. Theoretical modeling shows that (√7 × 3)R19.1° reconstruction, previously unknown Ce3O5 stoichiometry, stabilized at but cannot be assigned bulk structure. Statistical explains thermodynamic stability phases depending on chemical potential coexistence certain over range temperatures. These results are crucial understanding geometric electronic structure–function correlations nanostructured rational design novel ceria-based functional systems.