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arXiv · 1608.05833

CO-Induced Restructuring on Stepped Pt Surfaces: A Molecular Dynamics Study

Joseph R. Michalka·Andrew P. Latham·J. Daniel Gezelter
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Abstract

The effects of plateau width and step edge kinking on carbon monoxide (CO)-induced restructuring of platinum surfaces were explored using molecular dynamics (MD) simulations. Platinum crystals displaying four different vicinal surfaces [(321), (765), (112), and (557)] were constructed and exposed to partial coverages of carbon monoxide. Platinum-CO interactions were fit to recent experimental data and density functional theory (DFT) calculations, providing a classical interaction model that captures the atop binding preference on Pt. The differences in Pt-Pt binding strength between edge atoms on the various facets were found to play a significant role in step edge wandering and reconstruction events. Because the mechanism for step doubling relies on a stochastic meeting of two wandering edges, the widths of the plateaus on the original surfaces was also found to play a role in these reconstructions. On the Pt(321) surfaces, the CO adsorbate was found to assist in reordering the kinked step edges into straight {100} edge segments.

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Joseph R. Michalka, Andrew P. Latham, J. Daniel Gezelter. 2016-08-20. CO-Induced Restructuring on Stepped Pt Surfaces: A Molecular Dynamics Study. https://doi.org/10.1021/acs.jpcc.6b06619

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