Eur. Phys. J. D 43, 189-192 (2007)
https://doi.org/10.1140/epjd/e2007-00062-4

Catalyst poisoning in the conversion of CO and N₂O to CO₂ and N₂ on Pt₄^- in the gas phase

¹ Department Chemie, Lehrstuhl 2 für Physikalische Chemie, Technische Universität München, Lichtenbergstrasse 4, 85747 Garching, Germany
² Department of Chemistry and Centre for Research in Mass Spectrometry, York University, 4700 Keele Street, M3J1P3, Toronto Ontario, Canada
³ Institut für Chemie, Sekr. C4, Technische Universität Berlin, Strasse des 17 Juni 135, 10623 Berlin, Germany

Corresponding author: ^a martin.beyer@mail.chem.tu-berlin.de

Received: 23 July 2006
Revised: 13 October 2006
Published online: 24 May 2007

Abstract

Pt₄^- catalyses the conversion of CO and N₂O to CO₂ and N₂ in the gas phase, as observed by Fourier transform ion cyclotron (FT-ICR) mass spectrometry. The partial pressures of CO and N₂O determine the extent of poisoning and the turnover numbers that can be achieved. The catalytic conversion terminates as soon as two CO are adsorbed on the cluster. With N₂O, the reactivity of Pt₄O₂^- and Pt₄O₃^- is reduced to 41% and 34% compared to Pt₄O^-, respectively, and with Pt₄O₄^- this value is reduced to 1%. In contrast, Pt₄⁺ shows no apparent catalytic activity. Density functional theory calculations of Pt₄^+/- with CO and N₂O adsorbates reveal significantly different stabilities of the reaction intermediates for the different charge states.