Details

Autor(en) / Beteiligte

• Maslakov, Konstantin I.
• Teterin, Yury A.
• Popel, Aleksej J.
• Teterin, Anton Yu
• Ivanov, Kirill E.
• Kalmykov, Stepan N.
• Petrov, Vladimir G.
• Petrov, Peter K.
• Farnan, Ian

Titel

XPS study of ion irradiated and unirradiated CeO2 bulk and thin film samples

Ist Teil von

• Applied surface science, 2018-08, Vol.448, p.154-162

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• [Display omitted] •The oxidation state of the cerium ion in CeO2 was clarified.•A complex structure of the XPS spectra for the inner Ce electrons was clarified.•A quantitative Ce ionic composition (Ce3+, Ce4+) on the surface of CeO2 obtained.•Ion irradiation increased the Ce3+ content in thin film and bulk CeO2 samples. This work considers the effect of fission-energy ion irradiation on the electronic structure at the surface of bulk and thin film samples of CeO2 as a simulant for UO2 nuclear fuel. For this purpose, thin films of CeO2 grown on Si substrates and bulk CeO2 samples were irradiated by Xe ions (92 MeV, 4.8 × 1015 ions/cm2) to simulate the fission damage that occurs within nuclear fuels. The irradiated and unirradiated samples were characterized by X-ray photoelectron spectroscopy. A technique of the quantitative evaluation of cerium ionic composition on the surface of the samples has been successfully applied to the obtained XPS spectra. This technique is based on the intensity of only one of the reliably identifiable high-energy peak at 916.6 eV in the Ce 3d XPS spectra. The as-produced samples were found to contain mostly the Ce4+ ions with a small fraction of Ce3+ ions formed on the surface in the air or under X-rays. The core-electron XPS structure of CeO2 was associated with the complex final state with vacancies (holes) resulting from the photoemission of an inner electron. The Xe ion irradiation was found to increase the Ce3+ content in the samples of CeO2, with the thin films being more sensitive than the bulks samples.