Nickeltetracarbonyl formation on non-equilibrium Ni surfaces

• Published in: Surface science Vol. 401; no. 1; pp. L371 - L374
• Main Authors: Medvedev, V.K, Börner, R, Kruse, N
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 20.03.1998; Amsterdam Elsevier Science; New York, NY
• Subjects: Auger electron spectroscopy; Carbon monoxide; Chemistry; Exact sciences and technology; General and physical chemistry; Nickel; Nickelcarbonyl; Solid-gas interface; Surface physical chemistry; Auger electron spectroscopy; Nickel; Carbon monoxide; Nickelcarbonyl; Chemisorption; Carbonylation; Surface reaction; Gas solid interface; Experimental study; Auger electron spectrometry
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/S0039-6028(98)00040-5

The subject of this investigation was the kinetics of Ni volatilization in form of nickeltetracarbonyl (Ni(CO) 4) during the interaction of CO gas with a Ni foil at room temperature (or slightly above). A trap-decomposition technique on an auxiliary Rh surface and posterior Auger spectroscopy were used for the product analysis. The presence of a high step site density (kinks) on an intentionally roughened Ni surface was found to cause a strong rate enhancement. CO pressures as low as 5×10 −5 mbar turned out to be sufficient for the reaction to occur. However, a well-annealed equilibrium Ni surface remained inactive in Ni(CO) 4 formation under these conditions. A reaction model is presented by taking into account the present-day knowledge about Ni-subcarbonyl intermediate formation.