Faceting of Rhodium(553) in Realistic Reaction Mixtures of Carbon Monoxide and Oxygen
Artikel i vetenskaplig tidskrift, 2015
We have investigated the gas composition-dependent faceting of a Rh(553) surface during catalytic CO oxidation under semirealistic reaction conditions using Surface X- ray Diffraction. We find that under stoichiometric CO and O2 conditions, the Rh(553) surface maintains its surface orientation without facet formation. In oxygen excess, the CO oxidation reaction becomes mass transfer limited by the CO diffusion, and the sur- face is observed to expose (331) or (11 ̄1) facets in coexistence with larger (111) terraces. The observed facet formation has previously been observed for pure O2 exposures of the Rh(553) surface, but at significantly lower O2 partial pressures. Surprisingly, in CO excess, which results in a CO poisoned surface with low activity, we instead find coexisting (110) and (111) facets. The reasons for and possible implications of the observed facetings are discussed.
CO oxidation
vicinal surface
Surface X-ray diffraction
Författare
Chu Zhang
Lunds universitet
Edvin Lundgren
Lunds universitet
Per-Anders Carlsson
Chalmers, Kemi och kemiteknik, Tillämpad kemi
Kompetenscentrum katalys
Olivier Balmes
Lunds universitet
Anders Hellman
Kompetenscentrum katalys
Lindsay R. Merte
Lunds universitet
Mikhail Shipilin
Lunds universitet
Willem Onderwaater
European Synchrotron Radiation Facility (ESRF)
Universiteit Leiden
Johan Gustafson
Lunds universitet
Journal of Physical Chemistry C
1932-7447 (ISSN) 1932-7455 (eISSN)
Vol. 119 21 11646-11652Tidsupplösta in situ metoder för design av katalytiska säten för hållbar kemi
Vetenskapsrådet (VR) (2013-567), 2013-01-01 -- 2016-12-31.
Drivkrafter
Hållbar utveckling
Styrkeområden
Nanovetenskap och nanoteknik
Transport
Energi
Materialvetenskap
Ämneskategorier
Fysikalisk kemi
Den kondenserade materiens fysik
DOI
10.1021/acs.jpcc.5b01841