Details
| Original language | English |
|---|---|
| Pages (from-to) | 33-37 |
| Number of pages | 5 |
| Journal | Catalysis letters |
| Volume | 86 |
| Issue number | 1-3 |
| Publication status | Published - Mar 2003 |
Abstract
Ammonia oxidation with oxygen over Pt(533) in the pressure range 10 -7-10-3mbar has been studied using LEED and scanning tunneling microscopy (STM) to detect reaction-induced structural changes. Below 620 K, strong hysteresis effects in the rate occur upon cyclic variation of one of the p, T parameters. The rate changes are associated with structural modifications of the substrate. The Pt(533) surface exhibiting single atomic steps after preparation undergoes a doubling in step height and terrace width connected with a shift in selectivity from preferential N2 production to strong NO formation. Restoring the single atomic steps in vacuum requires heating above 1100 K, but under reaction conditions the substrate changes are reversible at least down to 600 K.
Keywords
- Ammonia oxidation, Catalyst restructuring, Hysteresis effects, Scanning tunneling microscopy, Stepped Pt surface
ASJC Scopus subject areas
- Chemical Engineering(all)
- Catalysis
- Chemistry(all)
- General Chemistry
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: Catalysis letters, Vol. 86, No. 1-3, 03.2003, p. 33-37.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Selectivity changes due to restructuring of the Pt(533) surface in the NH3 + O2 reaction
AU - Scheibe, A.
AU - Günther, S.
AU - Imbihl, R.
N1 - Funding Information: This work was supported by the DFG under the priority program 1091 ‘‘Bridging the gap between ideal and real systems in heterogeneous catalysis’’.
PY - 2003/3
Y1 - 2003/3
N2 - Ammonia oxidation with oxygen over Pt(533) in the pressure range 10 -7-10-3mbar has been studied using LEED and scanning tunneling microscopy (STM) to detect reaction-induced structural changes. Below 620 K, strong hysteresis effects in the rate occur upon cyclic variation of one of the p, T parameters. The rate changes are associated with structural modifications of the substrate. The Pt(533) surface exhibiting single atomic steps after preparation undergoes a doubling in step height and terrace width connected with a shift in selectivity from preferential N2 production to strong NO formation. Restoring the single atomic steps in vacuum requires heating above 1100 K, but under reaction conditions the substrate changes are reversible at least down to 600 K.
AB - Ammonia oxidation with oxygen over Pt(533) in the pressure range 10 -7-10-3mbar has been studied using LEED and scanning tunneling microscopy (STM) to detect reaction-induced structural changes. Below 620 K, strong hysteresis effects in the rate occur upon cyclic variation of one of the p, T parameters. The rate changes are associated with structural modifications of the substrate. The Pt(533) surface exhibiting single atomic steps after preparation undergoes a doubling in step height and terrace width connected with a shift in selectivity from preferential N2 production to strong NO formation. Restoring the single atomic steps in vacuum requires heating above 1100 K, but under reaction conditions the substrate changes are reversible at least down to 600 K.
KW - Ammonia oxidation
KW - Catalyst restructuring
KW - Hysteresis effects
KW - Scanning tunneling microscopy
KW - Stepped Pt surface
UR - http://www.scopus.com/inward/record.url?scp=0037367515&partnerID=8YFLogxK
U2 - 10.1023/A:1022646622343
DO - 10.1023/A:1022646622343
M3 - Article
AN - SCOPUS:0037367515
VL - 86
SP - 33
EP - 37
JO - Catalysis letters
JF - Catalysis letters
SN - 1011-372X
IS - 1-3
ER -