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CO oxidation on a single Pd atom supported on magnesia

S. Abbet·U. Heiz·H. Hakkinen·U. Landman
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Abstract

The oxidation of CO on single Pd atoms anchored to MgO(100) surface oxygen vacancies is studied with temperature-programmed-reaction mass-spectrometry and infrared spectroscopy. In one-heating-cycle experiments CO$_2$, formed from O$_2$ and CO preadsorbed at 90 K, is detected at 260 K and 500 K. Ab-initio simulations suggest two reaction routes, with Pd(CO)$_2$O$_2$ and Pd(CO$_3$)CO found as precursors for the low and high temperature channels, respectively. Both reactions result in annealing of the vacancy and induce migration and coalescence of the remaining Pd-CO to form larger clusters.

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S. Abbet, U. Heiz, H. Hakkinen, U. Landman. 2001-05-23. CO oxidation on a single Pd atom supported on magnesia. https://doi.org/10.1103/physrevlett.86.5950

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