The chemistry of acetylene on the Ru(001)-p(2 times 2)O and Ru(001)-p(1 times 2)O surfaces

Journal Article · Wed Nov 23 00:00:00 EST 1988 · Journal of the American Chemical Society; (USA)

DOI:https://doi.org/10.1021/ja00232a002· OSTI ID:5093748

Parmeter, J E; Hills, M M; Weinberg, W H ^[1]

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1. California Institute of Technology, Pasadena (USA)

The chemisorption and decomposition of acetylene on Ru(001) surfaces with ordered p(2{times}2) and p(1{times}2) overlayers of oxygen adatoms has been studied by using high-resolution electron energy loss spectroscopy and thermal desorption mass spectrometry. The chemisorbed acetylene species formed on these oxygen precovered surfaces are not significantly different from molecularly chemisorbed acetylene on clean Ru(001), although one of the two types of chemisorbed acetylene formed on the clean surface is not formed on Ru(001)-p(1{times}2)O. The preadsorption of oxygen reduces the saturation coverages of chemisorbed acetylene, which is approximately 0.39 on clean Ru(001), 0.31 on Ru(001)-p(2{times}2)O, and 0.09 on Ru(001)-p(1{times}2)O. As on clean Ru(001), the chemisorbed acetylene on the oxygen-precovered surfaces does not desorb upon annealing but rather decomposes between 200 and 350 K to produce a number of stable intermediates, including ethylidyne (CCH{sub 3}), acetylide (CCH), methylidyne (CH), and an sp{sup 2}-hybridized vinylidene (CCH{sub 2}) species. The vinylidene is formed in particularly large amounts on Ru(001)-p(2{times}2)O after annealing to 350 K and appears to be stabilized strongly by the presence of coadsorbed oxygen because it is formed not at all or in trivial amounts on clean Ru(001). The stability, formation, and decomposition of the various intermediates is discussed, and the results are compared with earlier work. The decomposition of all of these intermediates leads eventually to hydrogen desorption, which is complete on both oxygen-precovered surfaces by approximately 700 K. 26 refs., 7 figs., 2 tabs.

• OSTI ID: 5093748
• Journal Information: Journal of the American Chemical Society; (USA), Vol. 110:24; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ACETYLENE
CHEMISORPTION
RUTHENIUM OXIDES
SORPTIVE PROPERTIES
DECOMPOSITION
EXPERIMENTAL DATA
ALKYNES
CHALCOGENIDES
CHEMICAL REACTIONS
DATA
HYDROCARBONS
INFORMATION
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REFRACTORY METAL COMPOUNDS
RUTHENIUM COMPOUNDS
SEPARATION PROCESSES
SORPTION
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS
400201* - Chemical & Physicochemical Properties