Fronts and fluctuations in a tailored model for CO oxidation on metal(100) surfaces

TitleFronts and fluctuations in a tailored model for CO oxidation on metal(100) surfaces
Publication TypeJournal Article
Year of Publication2007
AuthorsLiu DJ, Evans JW
Journal TitleJournal of Physics-Condensed Matter
Date PublishedFeb
Type of ArticleArticle
ISBN Number0953-8984
Accession NumberISI:000243809700030
KeywordsADLAYERS, adsorption, behavior, diffusion, kinetics, oxygen, PD(100), phase-transitions, PT(111), simulation

An atomistic lattice-gas model is developed for CO oxidation on unreconstructed metal (100) surfaces. The model is tailored to incorporate the most essential features of such systems: multiple adsorption sites; short-ranged repulsive adspecies interactions; highly mobile CO; and the appropriate Langmuir-Hinshelwood adsorption-desorption and reaction kinetics. The model is applied to analyse both reaction front propagation on extended surfaces and fluctuation phenomena in nanoscale reaction systems. Contrasting conventional ultra-high-vacuum studies, we focus on behaviour at higher pressures or lower temperatures where higher adspecies coverages can result in phase separation of the reactive state into a c(2 x 2)-O-rich ordered state and an intermixed CO + O state. This phenomenon can produce sharp reaction fronts in extended systems and fluctuation-induced transitions between phase-separated states in nanoscale systems.

Alternate JournalJ. Phys.-Condes. Matter