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 CO2, formed from O2 and CO preadsorbed at 90 K, is detected at 260 K and 500 K. Ab-initio simulations suggest two reaction routes, with Pd(CO)2O2 and Pd(CO3)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.
@article{arxiv.cond-mat/0105460,
title = {CO oxidation on a single Pd atom supported on magnesia},
author = {S. Abbet and U. Heiz and H. Hakkinen and U. Landman},
journal= {arXiv preprint arXiv:cond-mat/0105460},
year = {2009}
}
Comments
4 pages, 3 figures, scheduled for publication in PRL 18 June 2001