Interaction of formamide with the Ru(001) surface

Journal Article · Tue Jan 05 23:00:00 EST 1988 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00209a008· OSTI ID:7004901

Parmeter, J E; Schwalke, U; Weinberg, W H

The adsorption and decomposition of formamide (NH/sub 2/CHO) on the hexagonally close-packed Ru(001) surface have been studied by using high-resolution electron energy loss spectroscopy and thermal desorption mass spectrometry. At 80 K, the initial adsorption of formamide results in CH bond cleavage and the formation of an eta/sup 2/(C,O)-NH/sub 2/CO species. This species decomposes upon annealing to 250 K, leaving a mixture of CO, NH/sub 3/, NH, and hydrogen adatoms on the surface. The NH/sub 3/ and CO desorb near 315 and 480 K, respectively, whereas the NH decomposes below 400 K to nitrogen and hydrogen adatoms. Recombinative desorption of H/sub 2/ occurs at 420 K, while recombinative desorption of N/sub 2/ occurs near 770 K. For higher initial formamide coverages (where the fractional coverage of formamide that decomposes exceeds approximately 0.05 monolayer), molecular adsorption in an eta/sup 1/(O)-NH/sub 2/CHO configuration is observed also at 80 K. This species undergoes competing desorption and decomposition at 225 K to an intermediate believed to be N-bonded NHCHO, which in turn converts to a species tentatively identified as eta/sup 1/(N)-NCHO at 300 K. The latter species decomposes to chemisorbed CO, N, and H near 375 K. Following a saturation formamide exposure on Ru(001) at 80 K, approximately 0.15 monolayer of formamide decomposes upon subsequent annealing, with approximately two-thirds of the total decomposing via the eta/sup 2/(C,O)-NH/sub 2/CO intermediate and the remainder reacting via the eta/sup 1/(O)-NH/sub 2/CHO.

• Research Organization: California Institute of Technology, Pasadena (USA)
• OSTI ID: 7004901
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 110:1; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADSORPTION
AMIDES
CHEMICAL REACTIONS
DATA
DECOMPOSITION
DESORPTION
ELECTRON SPECTROSCOPY
ELEMENTS
ENERGY-LOSS SPECTROSCOPY
EXPERIMENTAL DATA
FORMAMIDE
HIGH TEMPERATURE
INFORMATION
LOW TEMPERATURE
MASS SPECTROSCOPY
MEDIUM TEMPERATURE
METALS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PLATINUM METALS
RUTHENIUM
SORPTION
SORPTIVE PROPERTIES
SPECTROSCOPY
SURFACE PROPERTIES
SURFACES
TEMPERATURE DEPENDENCE
TRANSITION ELEMENTS