(560gk) Descriptor-Based Modeling of CO Oxidation over Alumina-Supported Single Metal Atoms

Authors: 
Alexopoulos, K., University of Delaware
Vlachos, D. G., University of Delaware
Single atom catalysts receive extensive attention for reducing noble metal utilization and potential elimination of side reactions. Yet, the rational design of highly reactive and stable single atom catalysts is hampered by the current lack of fundamental insights at the single atom limit. In order to develop a descriptor-based modeling approach for single atom catalysis, the governing reaction mechanisms and scaling relations need to be identified first. To this end, density functional theory calculations are performed in this study for a prototype reaction, namely CO oxidation, over different single metal atoms supported on alumina. As expected for oxidation reactions, a large change in the oxophilicity of the supported single atom can have an important effect on the reaction mechanism. Hence, a novel descriptor-based modeling approach is developed in the present work using several correlations without a priori assumptions about rate-determining steps and most abundant reaction intermediates. In addition, the stability of the single atom catalysts is also accounted for in conjunction to their reactivity. In that respect, we find that atomically dispersed iron on alumina is a promising and relatively stable non-platinum group metal (non-PGM) alternative for low temperature CO oxidation.

Acknowledgements: This work is performed in the framework of the PARTIAL-PGMs project – funded by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 686086.