TY - JOUR
T1 - ESCA studies of metal-oxygen surfaces using argon and oxygen ion-bombardment
AU - Kim, K. S.
AU - Baitinger, W. E.
AU - Amy, J. W.
AU - Winograd, N.
N1 - Funding Information:
ACKNOWLEDGMENT The authors wish to thank the National Science Foundation (Grant No. GP-37017X and Materials Research Program Grant No. GH-33574Al) and the Air Force Office of Scientific Research (Grant No. AFOSR-72-2238) for financial support.
PY - 1974
Y1 - 1974
N2 - ESCA has been used to monitor alterations of catalytically and electrochemically important metal-oxygen surfaces following exposure to Ar+ and O2+ ion bombardment. This treatment resulted not only in sputtering, but also, in many cases, in reduction to the corresponding metal or lower oxide. A model based on bulk thermodynamic free energy considerations Is proposed to explain this phenomenon. We have also exploited this approach to obtain an in-depth concentration profile of various oxidation states of an element, to selectively prepare desired surface oxide compositio and to aid in interpreting complex O ls spectra. Results obtained from metal-oxygen surfaces for Ni, Ru and Mo are presented. Ni2O3 and RuO3, which are gross defect structures of the bulk species, are present on NiO and RuO2 respectively, with the former being confined to the surface layers. The MoO2, on the other hand, is covered with a surface layer of MoO3 present as a regular crystal structure.
AB - ESCA has been used to monitor alterations of catalytically and electrochemically important metal-oxygen surfaces following exposure to Ar+ and O2+ ion bombardment. This treatment resulted not only in sputtering, but also, in many cases, in reduction to the corresponding metal or lower oxide. A model based on bulk thermodynamic free energy considerations Is proposed to explain this phenomenon. We have also exploited this approach to obtain an in-depth concentration profile of various oxidation states of an element, to selectively prepare desired surface oxide compositio and to aid in interpreting complex O ls spectra. Results obtained from metal-oxygen surfaces for Ni, Ru and Mo are presented. Ni2O3 and RuO3, which are gross defect structures of the bulk species, are present on NiO and RuO2 respectively, with the former being confined to the surface layers. The MoO2, on the other hand, is covered with a surface layer of MoO3 present as a regular crystal structure.
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U2 - 10.1016/0368-2048(74)85023-1
DO - 10.1016/0368-2048(74)85023-1
M3 - Article
AN - SCOPUS:0000538358
SN - 0368-2048
VL - 5
SP - 351
EP - 367
JO - Journal of Electron Spectroscopy and Related Phenomena
JF - Journal of Electron Spectroscopy and Related Phenomena
IS - 1
ER -