Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-28T17:09:08.076Z Has data issue: false hasContentIssue false
  • English
  • Français

Surface and bulk characterization of Rh/ZrO2 prepared by absorption of Rh4(CO)12 clusters on ZrO2 powder

Published online by Cambridge University Press:  03 February 2012

L. E. Depero ,
R. Bertoncello ,
T. Boni ,
P. Levrangi ,
I. Natali Sora ,
E. Tempesti  and
F. Parmigiani
L. E. Depero
Affiliation:
INFM and Department of Materials Chemistry and Physics, University of Brescia, Brescia, Italy
R. Bertoncello
Affiliation:
Department of Inorganic, Metallorganic and Analytical Chemistry, University of Padua, Padua, Italy
T. Boni
Affiliation:
Department of Materials Science, CISE S.p.A., Milano, Italy
P. Levrangi
Affiliation:
INFM and Department of Materials Chemistry and Physics, University of Brescia, Brescia, Italy
I. Natali Sora
Affiliation:
INFM and Department of Materials Chemistry and Physics, University of Brescia, Brescia, Italy
E. Tempesti
Affiliation:
INFM and Department of Materials Chemistry and Physics, University of Brescia, Brescia, Italy
F. Parmigiani*
Affiliation:
Department of Physics, Polytechnic of Milan, P.zza Leonardo da Vinci 32, 20133 Milan, Italy
*
a)Author to whom correspondence should be addressed.
Get access

Abstract

Rh nanoparticles supported on ZrO2 powder were prepared by adsorbing Rh4(CO)12 clusters from hexane solution under Ar atmosphere. Four samples with Rh content ranging from 0.25 Rh wt.% up to 4.10 Rh wt.% were studied by x-ray diffraction (XRD), transmission electron microscopy (TEM), x-ray photoelectron spectroscopy (XPS), scanning Auger microscopy (SAM), and time of flight secondary ion mass spectroscopy (ToF-SIMS). TEM measurements show, for all the samples, Rh particles with a size of about 50 Å. The 4.10 Rh wt.% sample also shows some agglomerates of Rh nanoparticles and only for this sample Rh metallic phase was detected by XRD. The profile analysis of the XRD lines indicates an average size of the Rh crystallites of about 60 Å. XPS studies show only a single spectral component for the Zr3d5/2 core line at 182.2 eV. Instead, at least, two components at 307.2 eV and 308.5 eV are detected for the Rh3d5/2 core line. These results suggest that Zr is present only as oxidized state, whereas nonoxidized and oxidized Rh are both observed. A nonoxidized Rh state is also suggested by the XPS valence band electron removal spectrum which exhibits a significant emission within the ZrO2 band gap assigned to Rh 4d bands. A further support to this finding arises from scanning Auger maps of OKVV and RH where nonoxidized Rh is observed. Finally scanning Auger maps using the OKVV and the Zr emissions show surface regions where only the Zr Auger lines are detected, whereas on pure ZrO2 powder this effect is not observed. Since it is possible to rule out from the XPS Zr3d core line spectra, the presence of metallic zirconium hydrogen spillover mechanisms is invoked to explain this result.

Type
Articles
Information
Journal of Materials Research , Volume 12 , Issue 5 , May 1997 , pp. 1376 - 1384
Copyright
Copyright © Materials Research Society 1997

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Bagus, P. S., Brundle, C. R., Pacchioni, G., and Parmigiani, F., Surf. Sci. Report (1994), and refs. therein.Google Scholar
2.Parmigiani, F., Kay, E., Nelin, C. J., and Bagus, P. S., J. Electron. Spectrosc. Related Phenom. 36, 257 (1985).CrossRefGoogle Scholar
3.Mason, M. G., in Cluster Models for Surface and Bulk Phenomena, edited by Bagus, P. S., Pacchioni, G., and Parmigiani, F. (Plenum Press, New York, 1992), and refs. therein.Google Scholar
4. See, for example, Knözinger, H., in Cluster Models for Surface and Bulk Phenomena, edited by Bagus, P. S., Pacchioni, G., and Parmigiani, F. (Plenum Press, New York, 1992), and refs. therein.Google Scholar
5.Parmigiani, F., Kay, E., and Bagus, P. S., J. Electron. Spectrosc. and Related Phenomena 36, 257 (1985).CrossRefGoogle Scholar
6. “Catalysis by Acid and Bases,” Studies in Surface Science and Catalysis, edited by Imelik, B. (Elsevier, Amsterdam, 1985), Vol. 20; V. F. Kiselev and O. V. Krilov, Adsorption and Catalysis on Transition Metals and Their Oxides (Springer, Heidelberg, 1989).Google Scholar
7. See, for example, Zhang, Z., Jeng, S. P., and Henrich, V. E., Phys. Rev. B 43, 12004 (1991; W. Goper, J. A. Anderson, D. Frankel, M. Jaehnig, K. Phillips, J. A. Shafer, and G. Rocker, Surf. Sci. 139, 333 (1984); V. E. Henrich, Rept. Progr. Phys. 48, 1481 (1985).CrossRefGoogle Scholar
8.Dake, L. S. and Lad, R. J., Surf. Sci. 289, 297 (1993), and refs. therein.CrossRefGoogle Scholar
9.Zhang, Z. and Henrich, V. E., Surf. Sci. 277, 263 (1992).CrossRefGoogle Scholar
10.Neikam, W. C. and Vannice, M. A., J. Catal. 20, 260 (1971); 27, 207 (1972).Google Scholar
11.Kisel, V. F. and Krylov, O. V., Adsorption and Catalysis on Transition Metals and Their Oxides (Springer-Verlag, New York, 1989), p. 391.CrossRefGoogle Scholar
12.Often, G. J. Der and Davtzenberg, F. M., J. Catal. 53, 116 (1978).Google Scholar
13. See, for example, Oh, S. H., J. Catal. 124, 477 (1990).CrossRefGoogle Scholar
14.Ichikawa, M., Sekizawa, K., Shikakura, K., and Kawai, M., J. Mol. Catal. 11, 167 (1981); M. Ichikawa, Chem. Technol. 12, 647 (1982).CrossRefGoogle Scholar
15.van't Blik, H. F. J., van Zon, J. B. A., Huzinga, T., Vis, T. C., Koningsberger, D. C., and Prince, R., J. Am. Chem. Soc. 107, 3339 (1985).CrossRefGoogle Scholar
16.Primet, M., J. Chem. Soc. Faraday Trans. I 74, 2570 (1978).CrossRefGoogle Scholar
17.Zaki, M., Kunzmann, G., Gates, B. C., and Knözinger, H., J. Phys. Chem. 91, 1486 (1987).CrossRefGoogle Scholar
18.Parmigiani, F., Depero, L. E., Sangaletti, L., and Samoggia, G., J. Electron. Spectrosc. Related Phenom. 63, 1 (1993).CrossRefGoogle Scholar
19.Morinaga, M., Adachi, M., and Tsukada, H. M., J. Phys. Chem. Solids 44, 3011 (1983).CrossRefGoogle Scholar
20.Nandi, R. K., Kuo, H. K., Shosberg, W., Wissler, G., Cohen, J. B., and Crust, B., J. Appl. Crystallogr. 17, 22 (1984).CrossRefGoogle Scholar
21. The calculations were performed using two programs by Luterotti, L. and Scardi, P., General Peak Separation Routine–MARQFIT and Line Broadening Analysis by W.A.X.S. (1992).Google Scholar
22.Zocchi, M., Acta Crystallogr. A36, 164 (1980).CrossRefGoogle Scholar
23.Moulder, J. F., Stikle, W. F., Sobol, P. E., and Bomben, K. D., Handbook of X-Ray Photoelectron Spectroscopy, edited by Chastain, J. (Perkin-Elmer Co., Eden Prairie, MN, 1992).Google Scholar
24.Lindenberg, B., Berndtsson, A., Nilsson, R., Nyholm, R., and Exner, O., Acta Chem. Scand. A, 32, 353 (1978).CrossRefGoogle Scholar
25.Clark, T. A. and Rizkalla, E. N., Chem. Phys. Lett. 37, 523 (1976).CrossRefGoogle Scholar
26.Nyholm, R. and Martensson, N. J., J. Phys. C 13, L279 (1980).CrossRefGoogle Scholar
27.Nefedov, V. I., Firsov, M. N., and Shaplygin, I. S., J. Electron. Spectrosc. Related Phenom. 26, 65 (1982).CrossRefGoogle Scholar
28.van't Blik, H. F. J., van Zon, J. B. A. D., Huizinga, T., Vis, J. C., Koningsberger, D. C., and Prins, R.; J. Am. Chem. Soc. 107, 3139 (1985).CrossRefGoogle Scholar
29.Papacostantopoulos, D. A., Handbook of the Band Structure of Elemental Solids (Plenum Press, New York, 1986), p. 156.Google Scholar
30.Camagni, P., Depero, L. E., Parmiginai, F., and Sangaletti, L., in Solid State Ionics III, edited by Nazri, G-A., Tarascon, J-M., and Armand, M. (Mater. Res. Soc. Symp. Proc. 293, Pittsburgh, PA, 1993), p. 449.Google Scholar