The application of X-ray photoelectron spectroscopy for determining the chemical state of supported catalysts is discussed with particular reference to the system iron-praseodymium-alumina. The XPS studies are complicated by the variable valency, intermediate stoichiometrics and by the variety of structure possibilities in the iron-praseodymium-alumina system. Techniques to cope with differential charging of the sample are described and results presented for the surface characterization of hydrogen conditioned catalysts. Extensive reaction between the catalyst components is shown to occur. It is shown that praseodymium is incorporated in the alumina support and that the reaction of iron at this surface can be distinguished from the reaction in the unpromoted iron-alumina catalyst.
KeywordsBinding Energy Electron Binding Energy Differential Charge Praseodymium Oxide Unpromoted Catalyst
Unable to display preview. Download preview PDF.
- 2.B.G. Baker and M. Jasieniak, in Surface Science: Principles and Applications, in Springer Proceed, in Physics 73, ed. by R.F. Howe, R.N. Lamb and K. Wandelt, (Springer-Verlag 1993) pp. 279–289.Google Scholar
- 3.B.G. Baker, in Surface Analysis Methods in Material Science, Springer Ser. in Surface Sci. 23, ed by D.J. O’Connor, B.A. Sexton and R.St.C. Smart, (Springer-Verlag 1992) pp. 337–351.Google Scholar
- 6.R.L.N. Sastry, P.N. Mehrotra and C.N.R. Rao, J. Inorg. Nucl. Chem., 28, 1579 (1966).Google Scholar
- 8.W.J. Landis and J.R. Martin, J. Vacuum Sci. Technol., A2, 1108 (1984).Google Scholar
- 12.Handbook of X-ray Photoelectron Spectroscopy, ed. by J. Chastain, (Perkin-Elmer Corporation, Physical Electronics Division 1992).Google Scholar
- 13.L. Erying, in Handbook of the Physics and Chemistry of Rare Earth, Vol. 3, ed. by K.A. Gschneidner and Erying, (North-Holland Publishing Company 1979) pp. 337–399.Google Scholar