Abstract
Using polarization-modulated ellipsometry to monitor adsorbate coverage in-situ we studied the activated adsorption of filament-heated molecular hydrogen on Cu(111) and subsequent isothermal desorption of hydrogen adatoms. The adsorption is characterized by a zeroth-order kinetic with a constant sticking probability of S0=0.0062 up to θ=0.25 followed by a Langmuir kinetic until the saturation coverage θs=0.5 is reached. The desorption follows a second-order kinetic with an activation energy of 0.63 eV and a pre-exponential factor of 1×109 /s. A pre-adsorbed monolayer of Xe atoms on Cu(111) with a desorption activation energy of 0.25 eV and a pre-exponential factor of 8×1014 /s efficiently blocks the subsequent adsorption of hot molecular hydrogen making physisorbedXe useful as templates for spatial patterning of hydrogen adatom density on Cu(111).
Original language | English (US) |
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Pages (from-to) | 115-121 |
Number of pages | 7 |
Journal | Applied Physics A: Materials Science and Processing |
Volume | 86 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2007 |
ASJC Scopus subject areas
- Materials Science(all)
- Physics and Astronomy (miscellaneous)