Dynamics of catalytic ammonia oxidation over Rh(111) surfaces

• Applicant: Professor Dr. Ronald Imbihl
• Subject Area: Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 235516480

In this project we plan to study chemical wave patterns and kinetic instabilities in catalytic ammonia oxidation over a flat and a stepped Rh(111) surface, Rh(533). Photoemission electron microscopy (PEEM) and low energy electron microscopy (LEEM) shall be employed as spatially resolving in situ methods. The main motivation is to come to a mechanistic understanding of a new type of front instability we observed recently in a similar but structurally more complex system, Rh(110)/NH3 + O2. In the bistable regime this instability caused a sideways displacement of the interface which propagated in wave-like manner along the front line. A realistic model of the reaction system shall be developed. In parallel we will try to analyze the instabilities with a general model of an excitable reaction-diffusion system based on equations of the FitzHugh-Nagumo and of the Allen-Kahn type.

• DFG Programme: Research Grants
• International Connection: Argentina
• Partner Organisation: Consejo Nacional de Investigaciones Científicas y Técnicas
• Participating Persons: Dr. Matias Rafti; Professor Dr. Hannes Uecker