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arXiv · 1302.1388

In situ X-ray photoelectron spectroscopy of model catalysts: At the edge of the gap

S. Blomberg·M. J. Hoffmann·J. Gustafson·N. M. Martin·V. R. Fernandes·A. Borg·Z. Liu·R. Chang·S. Matera·K. Reuter·E. Lundgren
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Abstract

We present a High-Pressure X-ray Photoelectron Spectroscopy (HP-XPS) and first-principles kinetic Monte Carlo study addressing the nature of the active surface in CO oxidation over Pd(100). Simultaneously measuring the chemical composition at the surface and in the near-surface gas-phase, we reveal both O-covered pristine Pd(100) and a surface oxide as stable, highly active phases in the near-ambient regime accessible to HP-XPS. Surprisingly, no adsorbed CO can be detected during high CO2 production rates, which can be explained by a combination of a remarkably short residence time of the CO molecule on the surface and mass-transfer limitations in the present set-up.

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S. Blomberg, M. J. Hoffmann, J. Gustafson, N. M. Martin, V. R. Fernandes, A. Borg, Z. Liu, R. Chang, S. Matera, K. Reuter, E. Lundgren. 2013-02-06. In situ X-ray photoelectron spectroscopy of model catalysts: At the edge of the gap. https://doi.org/10.1103/physrevlett.110.117601

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