Surface interaction of PuO.sub.2./sub., UO.sub.2+x./sub. and UO.sub.3./sub. with water ice

0422399 - FZÚ 2014 RIV NL eng J - Journal Article
Gouder, T. - Shick, Alexander - Huber, F.
Surface interaction of PuO₂, UO_2+x and UO₃ with water ice.
Topics in Catalysis. Roč. 56, č. 12 (2013), s. 1112-1120. ISSN 1022-5528. E-ISSN 1572-9028
Institutional support: RVO:68378271
Keywords : photoemission * catalysis * surface oxidation
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.220, year: 2013

The interaction of PuO2, UO2+x and UO3 with water ice was studied using ultraviolet photoelectron spectroscopy (UPS). Water was adsorbed at 80-120 K as thick ice multilayers. Surface modification after desorption of the ice around 200 K was investigated. Main information on the surface oxidation state was obtained by highly surface sensitive UPS-HeII spectra, probing primarily the first monolayer. The oxidation state was directly deduced from the intensity of the actinide 5f levels. The surface character of the phenomenon was further confirmed by comparing HeII spectra with the more bulk sensitive HeI spectra. Spectral interpretation was done using the cross-section variations in HeI and HeII spectra and by comparing the spectra with theoretical density of states curves, obtained by LSDA + U calculations.
Permanent Link: http://hdl.handle.net/11104/0228537