Dehydrogenation of Cyclohexene on Platinum Nanoclusters on a Thin Film of Al2O3/NiAl(100)
- 100 Downloads
Using a scanning-tunneling microscope, reflection high-energy electron diffraction and photoelectron spectra with synchrotron radiation, we investigated the temperature dependence of the dehydrogenation of cyclohexene (C6H10) adsorbed on Pt nanoclusters supported on an ultra-thin film of Al2O3/NiAl(100). The Pt clusters, grown by vapor deposition, are structurally ordered and exhibit a mean diameter 2.2 nm and height 0.4 nm. The progress of dehydrogenation was monitored through the temporal variation of C 1s photoelectron spectra; analysis of these features revealed that the dehydrogenation of cyclohexene with increasing sample temperature occurs as a sequential process beginning around 150 K, a temperature significantly less than that for Pt single-crystal surfaces. The dehydrogenation behavior, particularly the decomposition into elemental carbon, is found to vary with Pt coverage.
KeywordsDehydrogenation Cyclohexene Pt Nanocluster STM PES
National Science Council (under grants NSC 94–2112-M-008-032 and NSC 95-2811-M-008-018) and National Synchrotron Radiation Research Centre of Taiwan supported this work. We thank M. H. Ten, W. R. Lin, C. I. Chiang and Z. F. Lin for their technical assistance in the experiments.
- 15.Santra AK, Goodman DW (2002) J Phys: Condens Matter 14:R31Google Scholar
- 24.Moulder JF, Stickle WF, Sobol PE, Bomben KD (1995) Handbook of x-ray photoelectron spectroscopy. Physical Electronics, Inc, USAGoogle Scholar
- 25.Yeh J-J (1993) Atomic calculation of photoionization cross sections and asymmetry parameters. A T & T Bell Laboratories, USAGoogle Scholar