Can oxygen vacancies in ceria surfaces be measured by O1s photoemission spectroscopy?

X-ray photoemission spectroscopy is a standard technique for materials characterization and the O 1s binding energy is commonly measured for oxides. Here we use density functional theory calculations to investigate how the O 1s binding energy in CeO2(111) is influenced by the presence of oxygen vacancies. The case with point vacancies in CeO2(111) is compared to complete reduction to Ce2O3. Reduction of CeO2 by oxygen vacancies is found to have a minor effect on the O 1s binding energy. The O 1s binding energy is instead clearly changed when the character of the chemical bond for the considered oxygen atom is modified by, for example, the formation of OH-groups or carbonates.

Automated summary

This study investigates the influence of oxygen vacancies on the O 1s binding energy in CeO2(111) using density functional theory calculations. Comparisons are made between point vacancies in CeO2(111) and complete reduction to Ce2O3. The results show that the reduction of CeO2 by oxygen vacancies has a minor effect on the O 1s binding energy, while the O 1s binding energy is clearly changed when the chemical bond character of the oxygen atom is modified, such as by the formation of OH-groups or carbonates.