ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The interaction of oxygen with Pt{110}(1×2) has been investigated using supersonic molecular beams and low-energy electron diffraction (LEED) at incident kinetic energies of 60–900 meV and surface temperatures from 170 to 1100 K. LEED studies indicate that at low exposures and low beam energies (〈190 meV) oxygen does not induce a reconstruction to (1×1). However at high exposures and low beam energies, a variable unit mesh dimension Frenkel–Kontorova domain structure is observed. Sticking probability measurements on the clean surface indicate that oxygen dissociative adsorption on Pt{110}(1×2) is a predominantly precursor mediated process. At low surface temperatures (〈200 K) and low beam energies, the precursor has a strong influence on the adsorption kinetics, and mixed islands of dioxygen and adatoms are formed. Adsorption at beam temperatures below 880 K produces two states in the the thermal desorption spectroscopy spectra, but at higher incident gas temperatures a new high temperature desorption state (Tp=1020 K) can be populated, which inhibits the formation of the usual dissociatively chemisorbed states at Tp=720 and 820 K. © 1998 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.477255
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