Abstract
The interaction of D2 O with a polycrystalline cerium surface, successfully cleaned by heavy Ar+ bombardment and annealing, was studied at 120 were observed at BE 530.3 (Ce2O3) and 532.7eV (adsorbed OD). When clean Ce at 120 K was exposed to D2 O, the O(1s) spectra were initial eV (adsorbed D2 O). For exposures greater than 10 Langmuir (L), a multilayer of ice grows and the O(1s) spectra become dominated by a peak at 5. The results of interaction with D2 O are compared with oxidation by O2. The significant differences are: (1) the absence of Ce(IV) when oxidati relatively small extent of oxidation that occurs when Ce is exposed to D2 O at 120 K, and (3) the larger chemical-shift of the Ce(III)-derived spec. The XPS studies of the interaction of D2 O with Ce reported here may be summarized as follows:. (1) Exposure at 300 K gives rise to O(1s) features characteristic of oxide and hydroxide, while the Ce(3d) spectra indicate Ce(III), but no CE(. (2) Exposure at 120 K gives O(1s) features characteristic of adsorbed OD, chemisorbed D2 O, a multilayer of ice, and a small amount of oxide. T are characteristic of clean Ce except for slight broadening. (3) Exposure at 120 K followed by warming to 240 and 300 K gives spectra characteristic of hydroxide and oxide surface-species. Between 240 and 300 K, O(1s) intensity. (4) At 300 K, a relatively thick layer of oxide forms, and after an exposure of 50 L the features characteristic of metallic Ce are no longer observabl. (5) As compared to the case for O2, exposure to D2 O gives rise to different satellite-splittings in the Ce(3d) spectra, suggesting that di formed in the two cases. (6) The spectra observed for Ce exposed to D2 O are in excellent accord with those found for the heavier lanthanides [4].
Original language | English (US) |
---|---|
Pages (from-to) | 31-46 |
Number of pages | 16 |
Journal | Journal of Electron Spectroscopy and Related Phenomena |
Volume | 21 |
Issue number | 1 |
DOIs | |
State | Published - 1980 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Radiation
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Spectroscopy
- Physical and Theoretical Chemistry