skip to main content

SciTech ConnectSciTech Connect

Title: CO oxidation on Pt(111) at near ambient pressures

The oxidation of CO on Pt(111) was investigated simultaneously by near ambient pressure X-ray photoelectron spectroscopy and online gas analysis. Different CO:O{sub 2} reaction mixtures at total pressures of up to 1 mbar were used in continuous flow mode to obtain an understanding of the surface chemistry. By temperature-programmed and by isothermal measurements, the onset temperature of the reaction was determined for the different reactant mixtures. Highest turnover frequencies were found for the stoichiometric mixture. At elevated temperatures, the reaction becomes diffusion-limited in both temperature-programmed and isothermal measurements. In the highly active regime, no adsorbates were detected on the surface; it is therefore concluded that the catalyst surface is in a metallic state, within the detection limits of the experiment, under the applied conditions. Minor bulk impurities such as silicon were observed to influence the reaction up to total inhibition by formation of non-platinum oxides.
Authors:
; ; ;  [1] ;  [2] ;  [1] ;  [3]
  1. Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen (Germany)
  2. MTA-SZTE Reaction Kinetics and Surface Chemistry Research Group, Rerrich Béla tér 1, 6720 Szeged (Hungary)
  3. (Germany)
Publication Date:
OSTI Identifier:
22493701
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 144; Journal Issue: 4; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CARBON MONOXIDE; CATALYSTS; CHEMISTRY; DIFFUSION; GAS ANALYSIS; IMPURITIES; MIXTURES; OXIDATION; PLATINUM; PLATINUM OXIDES; SENSITIVITY; STOICHIOMETRY; SURFACES; TEMPERATURE DEPENDENCE; X-RAY PHOTOELECTRON SPECTROSCOPY