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Some of the most important catalytic reactions involve the massive use
of catalysts based on precious metals like Platinum, Palladium or Rhodium
as active materials. Because of the overall extreme complexity of catalytic
reactions, the development of new catalysts has been largely carried out
so far by empirical “trial and error” methods. Overall, this
methodology has been fairly successful, yet it is very expensive, both
in terms of time and cost.
Present project’s main objective is the fabrication of new metal/metal
interfaces that will produce catalysts presenting the same chemical reactivity
as Palladium, which has shown very good performance as methanol synthesis
catalyst. It deals with a multi-technique characterization of the atomic
and electronic structure of ultra-thin pseudomorphic layers of model catalysts,
obtained by successive evaporations of Ru overlayers on a Ni single crystal
surface. The major structural technique is going to be atom-resolved Scanning
Tunnelling Microscopy (STM) measurements, as a function of the successive
number of Ru adlayers. STM is a very precise instrument to image with
atomic resolution. It will be used to investigate the quality of growth,
adsorption sites, and adsorption mechanism. Unwanted islands instead of
epitaxial layers may appear as well. Up to now, no STM investigations
were performed having as an investigative subject the Ru over Ni complex.
Characterization of electronic structure will be completed through high-resolution
X-Ray Photoelectron Spectroscopy (XPS) core level spectroscopy carried
out at a Synchrotron Radiation Facility (either in Saskatoon or at Elettra,
Trieste, Italy). These measurements will be correlated with measurements
of the system’s chemical reactivity, through Thermal Desorption
Spectroscopy measurements of probe molecules like H2, CO and O2.
The proposed work is part of a larger experimental effort going on at
INRS, dealing with the synthesis of novel core-shell catalytic nanoparticles
and their catalytic reactor tests, for methanol production from syngas.
Publications
P. Dorenbos, L. Pierron, L. Dinca, C.W.E. van Eijk, A.
Kahn-Harari and B. Viana, 4f–5d spectroscopy of Ce3+ in CaBPO5,
LiCaPO4 and Li2CaSiO4J, Phys.: Condens. Matter 15 No 3 (2003) 511-520
L.E. Dinca, P. Dorenbos, J.T.M. de Haas, V. R. Bom, C.W.E.
Van Eijk Nuclear, Alpha-gamma pulse shape discrimination in CsI:Tl, CsI:Na
and BaF2 scintillators, Instruments and Methods in Physics Research A,
486 (2002) 141-145.
L.E. Dinca, L. Gheorghe, A. Lupei, D. Pantelica, N. Scintee,
Growth, RBS-ERDA characterizations and modeling in Nd3+ doped calcium-lithium-niobium-gallium
garnet (CLNGG:Nd) crystal, Nuclear Instruments and Methods in Physics
Research A, 486 (2002) 93-97.
Education
M.Sc. - Bucharest University, Faculty of Physics, Romania - Nuclear Interactions
and Particles Physics
B.Sc. - Bucharest University, Faculty of Physics, Romania - Nuclear Applied
Physics
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