Abstract
[Ir4(CO)12] was used as a precursor for the preparation of a MgO-supported catalyst with a uniquely simple metal structure, Ir4. The precursor was adsorbed on MgO from hexanes with the metal framework remaining intact, as determined by extended X-ray absorption fine structure (EXAFS) spectra. The surface-bound species was inferred to be predominantly [HIr4(CO)11]−, which could be extracted from the surface by cation metathesis and identified in solution by infrared spectroscopy. After treatment of the MgO-supported iridium carbonyl in He followed by H2 at 300 °C, the sample was characterized again by EXAFS spectroscopy; the results provide evidence that the predominant surface species are clusters of four Ir atoms with an average Ir-Ir distance of 2.69 Å.
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References
B.C. Gates, L. Guczi and H. Knözinger, eds.,Metal Clusters in Catalysis (Elsevier, Amsterdam, 1986).
E. Iwasawa, ed.,Tailored Metal Catalysts (Reidel, Dordrecht, 1986).
H.H. Lamb, B.C. Gates and H. Knözinger, Angew. Chem. 27 (1988) 1127.
V.C. Henrich, Rep. Progr. Phys. 48 (1985) 1481.
F.W.H. Kampers, T.M.J. Maas, J. Van Grondelle, P. Brinkgreve and D.C. Koningsberger, Rev. Sci. Instrum. 60 (1989) 2635.
M. Angoletta, L. Malatesta and G. Caglio, J. Organomet. Chem. 94 (1975) 99.
J.W. Cook and D.E. Sayers, J. Appl. Phys. 52 (1981) 5024.
T.B.A.D. Van Zon, D.C. Koningsberger, H.F.J. Van't Blik and D.E. Sayers, J. Chem. Phys. 82 (1985) 5742.
F.B.M. Duivenvoorden, D.C. Koningsberger, Y.S. Uh and B.C. Gates, J. Am. Chem. Soc. 108 (1986) 6254.
F.B.M. Van Zon, Ph.D. Dissertation, Eindhoven University of Technology, 1988.
F.W.H. Kampers, Ph.D. Dissertation, Eindhoven University of Technology, 1988.
F.B.M. Van Zon, P.S. Kirlin, B.C. Gates and D.C. Koningsberger, J. Phys. Chem. 93 (1989) 2218.
F.B.M. Van Zon, G. Visser and D.C. Koningsberger,Proc. 9th Int. Congr. Catal. (Calgary) 3 (1988) 1386.
B.K. Teo and P.A. Lee, J. Am. Chem. Soc. 101 (1979) 2815.
M.R. Churchill and J.P. Hutchinson, Inorg. Chem. 17 (1978) 3528.
R. Bau, M.Y. Chiang, C.-Y. Wei, K. Garlaschelli, S. Martinengo and T.F. Koetzle, Inorg. Chem. 23 (1984) 4758.
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Maloney, S.D., Van Zon, F.B.M., Kelley, M.J. et al. A well-defined supported metal catalyst: Ir4/MgO. Catal Lett 5, 161–168 (1990). https://doi.org/10.1007/BF00763948
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DOI: https://doi.org/10.1007/BF00763948