Surface-Driven Electron Localization and Defect Heterogeneity in Ceria.

ABSTRACT: The exceptional performance of ceria (CeO₂) in catalysis and energy conversion is fundamentally governed by its defect chemistry, particularly oxygen vacancies. The formation of each oxygen vacancy (V_O^••) is assumed to be compensated by two localized electrons on cations (Ce³⁺). Here, we show by combining theory with experiment that while this 1 V_O^••: 2Ce³⁺ ratio accounts for the global charge compensation, it does not apply at the local scale, particularly in nanoparticles. Hybrid quantum mechanical/molecular mechanical (QM/MM) defect calculations, together with synchrotron X-ray photoelectron spectroscopy (XPS) measurements, show that electrons have a strong preference to localize and segregate on surfaces, whic

SUBMITTER: Zhang X 

PROVIDER: S-EPMC12447479 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature