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Title: Theoretical insight into Cobalt subnano-clusters adsorption on α-Al{sub 2}O{sub 3} (0001)

Abstract

The investigation on the structural stability, nucleation, growth and interaction of cobalt cluster Con(n=2–7) on the α-Al{sub 2}O{sub 3}(0001) surface by using density functional theory methods has been reported. Energetically, the most favorable adsorption sites were identified and the strongest adsorption energy cluster is the tetrahedral Co{sub 4} cluster. On the other hand, the nucleation of Con(n=2–7) clusters on the surface is exothermic and thermodynamically favorable. Moreover, even-odd alternation was found with respect to clusters nucleation as a function of the number of cobalt atoms (for n=1–7). Meanwhile, the Co{sub n} clusters can be adsorbed on the surface stably owing to the charge transfer from Co atoms to Al and O atoms of the Al{sub 2}O{sub 3} substrate. In addition, we establish the crucial importance of monomer, dimer and trimer diffusion on the surface. The diffusion of the monomer cobalt from Al{sup (3)} to O{sup (5)} or O{sup (5)} to Al{sup (4)} site is quite easy on the Al{sub 2}O{sub 3}(0001) surface, whereas the diffusion of the Co{sub 2} dimer is thermodynamically unfavorable by compared with that of the Co adatom and Co{sub 3} trimer. - Graphical abstract: Diffusion process of Co adatom on the α-Al{sub 2}O{sub 3} (0001) surface,more » Al{sup (3)} site→O{sup (5)} site→Al{sup (4)} site. Potential energy surface for diffusion of a single Co atom from Al{sup (3)} to O{sup (5)} site, and from O{sup (5)} to Al{sup (4)} site on the surface. The activation energy of the two migration processes from Al{sup (3)} to O{sup (5)} and O{sup (5)} to Al{sup (4)} are 0.06 and 0.09 eV, respectively. This implies the monomer is quite mobile on the surface under typical growth conditions.« less

Authors:
 [1];  [1];  [2];  [2]; ;  [2];  [1]
+ Show Author Affiliations
  1. College of Chemical Engineering and Environment, North University of China, 030051 Taiyuan (China)
  2. State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, 030001 Taiyuan (China)
Publication Date:
OSTI Identifier:
22658181
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 246; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACTIVATION ENERGY; ADSORPTION; ALUMINIUM OXIDES; CARBON DIOXIDE; CARBONATES; COBALT; DENSITY FUNCTIONAL METHOD; DIFFUSION; MONOMERS; NUCLEATION; OXIDATION; POTENTIAL ENERGY; SURFACES

Citation Formats

Gao, Fen-e, Ren, Jun, E-mail: jun.ren@nuc.edu.cn, Wang, Qiang, Li, Debao, E-mail: dbli@sxicc.ac.cn, Hou, Bo, Jia, Litao, and Cao, Duanlin. Theoretical insight into Cobalt subnano-clusters adsorption on α-Al{sub 2}O{sub 3} (0001). United States: N. p., 2017. Web. doi:10.1016/J.JSSC.2016.11.016.
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Gao, Fen-e, Ren, Jun, E-mail: jun.ren@nuc.edu.cn, Wang, Qiang, Li, Debao, E-mail: dbli@sxicc.ac.cn, Hou, Bo, Jia, Litao, & Cao, Duanlin. Theoretical insight into Cobalt subnano-clusters adsorption on α-Al{sub 2}O{sub 3} (0001). United States. doi:10.1016/J.JSSC.2016.11.016.
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Gao, Fen-e, Ren, Jun, E-mail: jun.ren@nuc.edu.cn, Wang, Qiang, Li, Debao, E-mail: dbli@sxicc.ac.cn, Hou, Bo, Jia, Litao, and Cao, Duanlin. Wed . "Theoretical insight into Cobalt subnano-clusters adsorption on α-Al{sub 2}O{sub 3} (0001)". United States. doi:10.1016/J.JSSC.2016.11.016.
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@article{osti_22658181,
title = {Theoretical insight into Cobalt subnano-clusters adsorption on α-Al{sub 2}O{sub 3} (0001)},
author = {Gao, Fen-e and Ren, Jun, E-mail: jun.ren@nuc.edu.cn and Wang, Qiang and Li, Debao, E-mail: dbli@sxicc.ac.cn and Hou, Bo and Jia, Litao and Cao, Duanlin},
abstractNote = {The investigation on the structural stability, nucleation, growth and interaction of cobalt cluster Con(n=2–7) on the α-Al{sub 2}O{sub 3}(0001) surface by using density functional theory methods has been reported. Energetically, the most favorable adsorption sites were identified and the strongest adsorption energy cluster is the tetrahedral Co{sub 4} cluster. On the other hand, the nucleation of Con(n=2–7) clusters on the surface is exothermic and thermodynamically favorable. Moreover, even-odd alternation was found with respect to clusters nucleation as a function of the number of cobalt atoms (for n=1–7). Meanwhile, the Co{sub n} clusters can be adsorbed on the surface stably owing to the charge transfer from Co atoms to Al and O atoms of the Al{sub 2}O{sub 3} substrate. In addition, we establish the crucial importance of monomer, dimer and trimer diffusion on the surface. The diffusion of the monomer cobalt from Al{sup (3)} to O{sup (5)} or O{sup (5)} to Al{sup (4)} site is quite easy on the Al{sub 2}O{sub 3}(0001) surface, whereas the diffusion of the Co{sub 2} dimer is thermodynamically unfavorable by compared with that of the Co adatom and Co{sub 3} trimer. - Graphical abstract: Diffusion process of Co adatom on the α-Al{sub 2}O{sub 3} (0001) surface, Al{sup (3)} site→O{sup (5)} site→Al{sup (4)} site. Potential energy surface for diffusion of a single Co atom from Al{sup (3)} to O{sup (5)} site, and from O{sup (5)} to Al{sup (4)} site on the surface. The activation energy of the two migration processes from Al{sup (3)} to O{sup (5)} and O{sup (5)} to Al{sup (4)} are 0.06 and 0.09 eV, respectively. This implies the monomer is quite mobile on the surface under typical growth conditions.},
doi = {10.1016/J.JSSC.2016.11.016},
journal = {Journal of Solid State Chemistry},
number = ,
volume = 246,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2017},
month = {Wed Feb 15 00:00:00 EST 2017}
}
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Journal Article:
DOI:  10.1016/J.JSSC.2016.11.016
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