CHEMISORPTIONANDREACTIVITYSTUDIESOFH, ANDCO ONSULFIDEDNi(100)
نویسندگان
چکیده
Sulfur segregation to the surface poses a perplexing problem in basic research on low surface area nickel materials. In addition sulfur effectively poisons catalytic reactions involving CO adsorption on nickel as well as other transition metal catalysts in technically important processes such as methanation and Fischer-Tropsch synthesis. It is not surprising then that considerable attention has been given the sulfur/nickel system [l--7]. For the Ni(l@O)/sulfur system investigators [ 6,7 ] using LEED, photoemission, as well as other techniques, agree that sulfur is chemisorbed with fourfold site coordination. The sulfur forms a ~(2 X 2) structure at one-quarter monolayer coverage and a c(2 X 2) structure at one-half monolayer. The one-half monolayer corresponds to a saturation coverage.
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