Abstract
Ultrafast near-infrared photoexcitation of mixed adlayers of carbon monoxide and atomic oxygen on the Pd(111) surface results in the efficient associative desorption of carbon dioxide. The oxidized fraction of the desorbed molecules ranges from ∼15% to 40%, approximately an order of magnitude greater than observed from Ru(001) under similar conditions. Time-resolved correlation measurements reveal fast dynamics that indicate the photochemistry is mediated by substrate electrons. The dynamics are strongly dependent on the initial CO coverage in a manner consistent with an activation energy for oxidation that depends on the initial CO binding site. These results, in addition to comparison of the ultrafast photooxidation to thermal oxidation, are consistent with the photooxidation occurring rapidly (within one to several picoseconds) from an initial mixed CO+O adlayer structure without time for diffusional phase segregation. The observed efficient ultrafast photoexcitation of associative desorption of CO2 from Pd(111) thus provides the opportunity to follow the picosecond dynamics of the bimolecular surface chemical reaction of CO+O from a well-defined initial geometry.
| Original language | English |
|---|---|
| Pages (from-to) | 15802-15808 |
| Number of pages | 7 |
| Journal | Journal of Physical Chemistry C |
| Volume | 112 |
| Issue number | 40 |
| DOIs | |
| Publication status | Published - Oct 9 2008 |
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ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Energy(all)
Cite this
Efficient subpicosecond photoinduced surface chemistry : The ultrafast photooxidation of CO on palladium. / Szymanski, P.; Harris, Alex; Camillone, N.
In: Journal of Physical Chemistry C, Vol. 112, No. 40, 09.10.2008, p. 15802-15808.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Efficient subpicosecond photoinduced surface chemistry
T2 - The ultrafast photooxidation of CO on palladium
AU - Szymanski, P.
AU - Harris, Alex
AU - Camillone, N.
PY - 2008/10/9
Y1 - 2008/10/9
N2 - Ultrafast near-infrared photoexcitation of mixed adlayers of carbon monoxide and atomic oxygen on the Pd(111) surface results in the efficient associative desorption of carbon dioxide. The oxidized fraction of the desorbed molecules ranges from ∼15% to 40%, approximately an order of magnitude greater than observed from Ru(001) under similar conditions. Time-resolved correlation measurements reveal fast dynamics that indicate the photochemistry is mediated by substrate electrons. The dynamics are strongly dependent on the initial CO coverage in a manner consistent with an activation energy for oxidation that depends on the initial CO binding site. These results, in addition to comparison of the ultrafast photooxidation to thermal oxidation, are consistent with the photooxidation occurring rapidly (within one to several picoseconds) from an initial mixed CO+O adlayer structure without time for diffusional phase segregation. The observed efficient ultrafast photoexcitation of associative desorption of CO2 from Pd(111) thus provides the opportunity to follow the picosecond dynamics of the bimolecular surface chemical reaction of CO+O from a well-defined initial geometry.
AB - Ultrafast near-infrared photoexcitation of mixed adlayers of carbon monoxide and atomic oxygen on the Pd(111) surface results in the efficient associative desorption of carbon dioxide. The oxidized fraction of the desorbed molecules ranges from ∼15% to 40%, approximately an order of magnitude greater than observed from Ru(001) under similar conditions. Time-resolved correlation measurements reveal fast dynamics that indicate the photochemistry is mediated by substrate electrons. The dynamics are strongly dependent on the initial CO coverage in a manner consistent with an activation energy for oxidation that depends on the initial CO binding site. These results, in addition to comparison of the ultrafast photooxidation to thermal oxidation, are consistent with the photooxidation occurring rapidly (within one to several picoseconds) from an initial mixed CO+O adlayer structure without time for diffusional phase segregation. The observed efficient ultrafast photoexcitation of associative desorption of CO2 from Pd(111) thus provides the opportunity to follow the picosecond dynamics of the bimolecular surface chemical reaction of CO+O from a well-defined initial geometry.
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U2 - 10.1021/jp8044737
DO - 10.1021/jp8044737
M3 - Article
VL - 112
SP - 15802
EP - 15808
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 40
ER -