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This study presents velocity-resolved desorption experiments of recombinatively-desorbing oxygen from Ag (111). We combine molecular beam techniques, ion imaging, and temperature-programmed desorption to obtain translational energy distributions of desorbing O 2 . Molecular beams of NO 2 are used to prepare a p (4 × 4)-O adlayer on the silver crystal. The translational energy distributions of O 2 are shifted towards hyperthermal energies indicating desorption from an intermediate activated molecular chemisorption state.
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Velocity map images of desorbing oxygen from sub-surface states of Rh(111)
We combine velocity map imaging (VMI) with temperature-programmed desorption (TPD) experiments to record the angular-resolved velocity distributions of recombinatively-desorbing oxygen from Rh(111). We assign the velocity distributions to desorption from specific surface and sub-surface states by matching the recorded distributions to the desorption temperature. These results provide insight into the recombinative desorption mechanisms and the availability of oxygen for surface-catalyzed reactions.
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- PAR ID:
- 10358844
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- ISSN:
- 1463-9076
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2CP03369K
