@article{39451,
  keywords = {oxidation, reduction, pattern-formation, chemical waves, platinum, NO reduction, peem, photoemission electron microscopy, Pt, Rh, co, bimetallic surface, nitric-oxide, scanning photoemission microscopy, dynamical imaging, electron-microscopy, microstructured composite   surfaces, spem},
  author = {Esch and Gunther and Schutz and Schaak and Kevrekidis and Marsi and Kiskinova and Imbihl},
  title = {Chemically resolved dynamical imaging of catalytic reactions on composite surfaces},
  abstract = { The catalytic reduction of NO by hydrogen is investigated at T = 650 K and p approximate to 10(-6) mbar on a microstructured Rh/Pt(100) surface consisting of Pt(100) domains surrounded by a 600 Angstrom thick Ph film. Synchrotron radiation scanning photoemission microscopy (SPEM), using photons focused into a spot of less than 0.2 mu m diameter, is employed as a spatially and chemically resolving in situ technique. The chemical waves which arise in the bistable system NO + H-2/Rh are imaged with SPEM monitoring the N ls and O ls photoelectrons. The reaction fronts initiate transitions from an inactive oxygen-covered surface (Theta(O) approximate to 0.25 ML) to a reactive nitrogen-covered surface (Theta(N) approximate to 0.06 ML). At the Pt/Ph interface, synergetic effects can be observed: the chemical waves on the Ph film nucleate preferentially at the Pt/Ph interface. This nucleation is poisoned by carbon contamination on the Pt area but is prevented in the vicinity of the Pt/Ph interface by the adjacent clean Ph film. No segregation of Pt to the surface was observed for the 600 Angstrom thick Ph film. },
  year = {1998},
  journal = {Catalysis LettersCatalysis Letters},
  volume = {52},
  pages = {85-90},
  isbn = {1011-372X},
  language = {English},
}