Campus Units
Mathematics, Ames Laboratory
Document Type
Article
Publication Version
Published Version
Publication Date
4-2001
Journal or Book Title
Physical Review B
Volume
63
Issue
16
First Page
165417-1
Last Page
165417-12
DOI
10.1103/PhysRevB.63.165417
Abstract
Local fluctuations and fluctuation-induced transitions in catalytic CO oxidation are studied with field electron microscopy on the (112) facets of a [100]-oriented Pt field emitter tip. The reaction is investigated in the bistable range close to the cusp point (critical point) that terminates the bistability range in pCO, T-parameter space. The amplitude and the spatial coherence of the fluctuations increase on approaching the critical point. The fluctuations are spatially well correlated on each flat (112) facet, but their correlation decays rapidly across stepped regions that terminate the flat facets. On smaller (112) facets, an onset of fluctuation-induced transitions is observed earlier (i.e., further away from the critical point) than for larger (112) facets. The behavior of the reaction system near the cusp point appears to be similar to that of an equilibrium system near the critical point. The observed fluctuations are mimicked in a simple reaction model for CO oxidation on surfaces that incorporates both rapid diffusion of adsorbed CO, and superlattice ordering of adsorbed immobile oxygen. The steady states of the model exhibit a cusp bifurcation, from a regime of bistability to one of monostability. The fluctuations increase near this cusp point, as in experiment. This behavior is analyzed via kinetic Monte Carlo simulations and analytic procedures, focusing on the consequences for fluctuation-induced transitions.
Copyright Owner
American Physical Society
Copyright Date
2001
Language
en
File Format
application/pdf
Recommended Citation
Suchorski, Yu; Beben, J.; James, E. W.; Liu, Da-Jiang; and Evans, James W., "Fluctuations and critical phenomena in catalytic CO oxidation on nanoscale Pt facets" (2001). Mathematics Publications. 11.
https://lib.dr.iastate.edu/math_pubs/11
Comments
This article is from Physical Review B 63 (2001): 165417, doi:10.1103/PhysRevB.63.165417 .