Details
| Original language | English |
|---|---|
| Pages (from-to) | 85-90 |
| Number of pages | 6 |
| Journal | Catalysis letters |
| Volume | 52 |
| Issue number | 1 |
| Publication status | Published - Jun 1998 |
Abstract
The catalytic reduction of NO by hydrogen is investigated at T = 650 K and p ≈ 10-6 CT mbar on a microstructured Rh/Pt(100) surface consisting of Pt(100) domains surrounded by a 600 Å thick Rh film. Synchrotron radiation scanning photoemission microcopy (SPEM), using photons focused into a spot of less then 0.2 μm diameter, is employed as a spatially and chemically resolving in situ technique. The chemical wave, which arise in the bistable system NO + H2/Rh are imaged with SPEM monitoring the N 1s and O 1s photoelectrons. The reaction fronts initiate transitions from an inactive oxygen-covered surface (ΘO ≈ 0.25 ML) to a reactive nitroeen-covered surface (ΘN ≈ 0.06 ML) At the Pt/Rh interface, synergetic effects can be observed: the chemical waves on the Rh film nucleate preferentially at the Pt/Rh interface. This nucleation is poisoned by carbon contamination on the Pt area but is prevented in the vicinity of the Pt/Rh interface by the adjacent clean Rh film. No segregation of Pt to the surface was observed for the 600 Å thick Rh film.
Keywords
- Chemical waves, Dynamical imaging, Microstructured composite surfaces, NO reduction, PEEM, Photoemission electron microscopy, Pt, Rh, Scanning photoemission microscopy, SPEM
ASJC Scopus subject areas
- Chemical Engineering(all)
- Catalysis
- Chemistry(all)
- General Chemistry
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In: Catalysis letters, Vol. 52, No. 1, 06.1998, p. 85-90.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Chemically resolved dynamical imaging of catalytic reactions on composite surfaces
AU - Esch, F.
AU - Günther, S.
AU - Schütz, E.
AU - Schaak, A.
AU - Kevrekidis, I. G.
AU - Marsi, M.
AU - Kiskinova, M.
AU - Imbihl, R.
PY - 1998/6
Y1 - 1998/6
N2 - The catalytic reduction of NO by hydrogen is investigated at T = 650 K and p ≈ 10-6 CT mbar on a microstructured Rh/Pt(100) surface consisting of Pt(100) domains surrounded by a 600 Å thick Rh film. Synchrotron radiation scanning photoemission microcopy (SPEM), using photons focused into a spot of less then 0.2 μm diameter, is employed as a spatially and chemically resolving in situ technique. The chemical wave, which arise in the bistable system NO + H2/Rh are imaged with SPEM monitoring the N 1s and O 1s photoelectrons. The reaction fronts initiate transitions from an inactive oxygen-covered surface (ΘO ≈ 0.25 ML) to a reactive nitroeen-covered surface (ΘN ≈ 0.06 ML) At the Pt/Rh interface, synergetic effects can be observed: the chemical waves on the Rh film nucleate preferentially at the Pt/Rh interface. This nucleation is poisoned by carbon contamination on the Pt area but is prevented in the vicinity of the Pt/Rh interface by the adjacent clean Rh film. No segregation of Pt to the surface was observed for the 600 Å thick Rh film.
AB - The catalytic reduction of NO by hydrogen is investigated at T = 650 K and p ≈ 10-6 CT mbar on a microstructured Rh/Pt(100) surface consisting of Pt(100) domains surrounded by a 600 Å thick Rh film. Synchrotron radiation scanning photoemission microcopy (SPEM), using photons focused into a spot of less then 0.2 μm diameter, is employed as a spatially and chemically resolving in situ technique. The chemical wave, which arise in the bistable system NO + H2/Rh are imaged with SPEM monitoring the N 1s and O 1s photoelectrons. The reaction fronts initiate transitions from an inactive oxygen-covered surface (ΘO ≈ 0.25 ML) to a reactive nitroeen-covered surface (ΘN ≈ 0.06 ML) At the Pt/Rh interface, synergetic effects can be observed: the chemical waves on the Rh film nucleate preferentially at the Pt/Rh interface. This nucleation is poisoned by carbon contamination on the Pt area but is prevented in the vicinity of the Pt/Rh interface by the adjacent clean Rh film. No segregation of Pt to the surface was observed for the 600 Å thick Rh film.
KW - Chemical waves
KW - Dynamical imaging
KW - Microstructured composite surfaces
KW - NO reduction
KW - PEEM
KW - Photoemission electron microscopy
KW - Pt
KW - Rh
KW - Scanning photoemission microscopy
KW - SPEM
UR - http://www.scopus.com/inward/record.url?scp=0542426193&partnerID=8YFLogxK
U2 - 10.1023/a:1019015302467
DO - 10.1023/a:1019015302467
M3 - Article
AN - SCOPUS:0542426193
VL - 52
SP - 85
EP - 90
JO - Catalysis letters
JF - Catalysis letters
SN - 1011-372X
IS - 1
ER -