Travelling fronts of the CO oxidation on Pd(111) with coverage-dependent diffusion

Journal Article · Tue Oct 28 00:00:00 EDT 2014 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4898705· OSTI ID:22310726

Cisternas, Jaime ^[1]; Karpitschka, Stefan ^[2]; Wehner, Stefan ^[3]

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1. Facultad de Ingeniería y Ciencias Aplicadas, Universidad de los Andes, Monseñor Alvaro del Portillo 12455, Las Condes, Santiago (Chile)
2. Physics of Fluids, University of Twente, Drienerlolaan 5, 7522 NB Enschede (Netherlands)
3. Institut für Integrierte Naturwissenschaften - Physik, Universität Koblenz-Landau, 56070 Koblenz (Germany)

In this work, we study a surface reaction on Pd(111) crystals under ultra-high-vacuum conditions that can be modeled by two coupled reaction-diffusion equations. In the bistable regime, the reaction exhibits travelling fronts that can be observed experimentally using photo electron emission microscopy. The spatial profile of the fronts reveals a coverage-dependent diffusivity for one of the species. We propose a method to solve the nonlinear eigenvalue problem and compute the direction and the speed of the fronts based on a geometrical construction in phase-space. This method successfully captures the dependence of the speed on control parameters and diffusivities.

• OSTI ID: 22310726
• Journal Information: Journal of Chemical Physics, Vol. 141, Issue 16; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBON MONOXIDE
CONTROL
CRYSTALS
DIFFUSION
DIFFUSION EQUATIONS
EIGENVALUES
ELECTRON EMISSION
MICROSCOPY
OXIDATION
PALLADIUM 111
PHASE SPACE
PRESSURE RANGE MICRO PA
SURFACES