Precursor state in the chemisorption of CO on supported palladium
clusters
J. Chem. Phys., (1991)DOI: 10.1063/1.461419
Abstract
It is demonstrated that physisorption of CO molecules on a MgO (100)
surface, supporting epitaxially grown Pd particles, acts as a precursor
state for CO chemisorption on the particles. The adsorption rate
of CO on the Pd particles is measured, at zero coverage by a molecular
beam technique, as a function of the substrate temperature and for
different particle sizes. A kinetic model describing the adsorption,
desorption, diffusion, and capture by the clusters of CO molecules
is given. Comparison with the experimental data gives the adsorption
probability: 0.5�0.05 and the saddle energy for surface diffusion:
0.25�0.05 eV of CO molecules on MgO. The Journal of Chemical Physics
is copyrighted by The American Institute of Physics.