Interaction of nitric oxide with reducing gases on the (100) plane of platinum

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5593327

Lesley, M W

The NO + CO and NO + H/sub 2/ reactions on Pt(100) were studied using temperature programmed desorption (TPD), isothermal desorption mass spectrometry, low energy electron diffraction (LEED), and x-ray photoelectron spectroscopy (XPS). Mathematical models were developed to describe the thermal desorption results. These models were then analyzed in an attempt to explain the rate oscillations which occur in the NO + CO reaction on polycrystalline platinum. TPD of NO and CO coadsorbed at 120 K yields almost complete reaction, with both N/sub 2/ and CO/sub 2/ products desorbing at approx. 410 K with full widths at half maximum as narrow as 3 K. Isothermal desorption mass spectrometry yields N/sub 2/ and CO/sub 2/ rates that exhibit a maximum with time. Both experiments indicate that the reaction mechanism is autocatalytic. TPD of NO coadsorbed with H/sub 2/ yields sharp N/sub 2/ and H/sub 2/O product peaks that closely resemble the N/sub 2/ and CO/sub 2/ peaks observed in the NO + CO reaction. LEED experiments during TPD and isothermal desorption of coadsorbed NO and CO indicated that the (1 x 1) ..-->.. hex substrate phase transformation sometimes accompanies desorption of N/sub 2/ and CO/sub 2/. XPS showed that molecular NO and molecular CO are the only species on the surface prior to the onset of reaction in thermal desorption experiments.

• Research Organization: Minnesota Univ., Minneapolis (USA)
• OSTI ID: 5593327
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010403* -- Coal & Coal Products-- Hydrogenation-- (-1987)
36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
ADSORPTION
AUGER ELECTRON SPECTROSCOPY
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTION KINETICS
COHERENT SCATTERING
CRYSTALS
DATA
DESORPTION
DIFFRACTION
ELECTRON DIFFRACTION
ELECTRON SPECTROSCOPY
ELEMENTS
EXPERIMENTAL DATA
HIGH TEMPERATURE
HYDROGEN
INFORMATION
KINETICS
LOW TEMPERATURE
MASS SPECTROSCOPY
MATHEMATICAL MODELS
METALS
NITRIC OXIDE
NITROGEN COMPOUNDS
NITROGEN OXIDES
NONMETALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PLATINUM
PLATINUM METALS
POLYCRYSTALS
REACTION INTERMEDIATES
REACTION KINETICS
SCATTERING
SORPTION
SPECTROSCOPY
SURFACE PROPERTIES
SURFACE TREATMENTS
TRANSITION ELEMENTS