@article{e4cbcb2b8084472e82ef26c751376ce9,
title = "Structure of Copper–Cobalt Surface Alloys in Equilibrium with Carbon Monoxide Gas",
abstract = "We studied the structure of the copper–cobalt (CuCo) surface alloy, formed by Co deposition on Cu(110), in dynamic equilibrium with CO. Using scanning tunneling microscopy (STM), we found that, in vacuum at room temperature and at low Co coverage, clusters of a few Co atoms substituting Cu atoms form at the surface. At CO pressures in the Torr range, we found that up to 2.5 CO molecules can bind on a single Co atom, in carbonyl-like configurations. Based on high-resolution STM images, together with density functional theory calculations, we determined the most stable CuCo cluster structures formed with bound CO. Such carbonyl-like formation manifests in shifts in the binding energy of the Co core-level peaks in X-ray photoelectron spectra, as well as shifts in the vibrational modes of adsorbed CO in infrared reflection absorption spectra. The multiple CO adsorption on a Co site weakens the Co–CO bond and thus reduces the C–O bond scission probability. Our results may explain the different product distribution, including higher selectivity toward alcohol formation, when bimetallic CuCo catalysts are used compared to pure Co.",
author = "Baran Eren and Daniel Torres and Osman Karslioglu and Zongyuan Liu and Wu, {Cheng Hao} and Dario Stacchiola and Hendrik Bluhm and Somorjai, {Gabor A.} and Salmeron, {Miquel B.}",
note = "This work was supported by the Office of Basic Energy Sciences (BES), Division of Materials Sciences and Engineering, of the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231, through the Structure and Dynamics of Materials Interfaces (FWP KC31SM). B.E. acknowledges support from the Abramson Family Center for Young Scientists. D.T. acknowledges support from PSC−CUNY Award, jointly funded by The Professional Staff Congress and The City University of New York and by the U.S. Department of Energy, Office of Workforce Development for Teachers and Scientists (WDTS) under the Visiting Faculty Program (VFP). The simulations were carried at the City University of New York High Performance Computing Center and at the National Energy Research Scientific Computing Center. This work also used the Extreme Science and Engineering Discovery Environment (XSEDE). D.T. would like to thank Stony Brook Research Computing and Cyberinfrastructure, and the Institute for Advanced Computational Science at Stony Brook University for access to the highperformance LIred and SeaWulf computing systems, the latter of which was made possible by a $1.4M National Science Foundation grant (#1531492). The APXPS experiments were carried out at BL11.0.2 of the Advanced Light Source, which is supported by the Office of Basic Energy Sciences, U.S. Department of Energy, under Contract No. DE-AC02-05CH11231. The IRRAS work at BNL was financed by the U.S. DOE, Office of Basic Energy Science (DE-SC0012704). H.B. and O.K. acknowledge support by the Director, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, of the U.S. Department of Energy under Contract DE-AC02-05CH11231.",
year = "2018",
month = may,
day = "30",
doi = "10.1021/jacs.7b13621",
language = "الإنجليزيّة",
volume = "140",
pages = "6575--6581",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "21",
}