Two-Dimensional Polymer Formation on Surfaces: Insight into the Roles of Precursor Mobility and Reactivity.
We report on a combined scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) study on the surface-assisted assembly of the hexaiodo-substituted macrocycle cyclohexa-m-phenylene (CHP) toward covalently bonded polyphenylene networks on Cu(111...
| Publicado en: | Journal of the American Chemical Society Vol. 132; no. 46; pp. 16669 - 16677 |
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| Autores principales: | , , , , , , , , , , , |
| Formato: | Artículo |
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American Chemical Society
11/24/2010
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| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=55570707&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 55570707 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 11/24/2010 vid: 132 iid: 46 pid: 997 pub: American Chemical Society artinfo: ui: 55570707 10.1021/ja107947z ppf: 16669 ppct: 8 formats: tig: atl: Two-Dimensional Polymer Formation on Surfaces: Insight into the Roles of Precursor Mobility and Reactivity. aug: au: Bieri, Marco Nguyen, Manh-Thuong Gröning, Oliver Cai, Jinming Treier, Matthias Aït-Mansour, Kamel Ruffieux, Pascal Pignedoli, Carlo A. Passerone, Daniele Kastler, Marcel Müllen, Klaus Fasel, Roman affil: Empa, Swiss Federal Laboratories for Materials Science and Technology, Feuerwerkerstrasse 39, CH-3602 Thun, and Ueberlandstrasse 129, CH-8600 Duebendorf Switzerland Institut de Science et d'Ingénierie Supramoléculaires (I.S.I.S.), Université de Strasbourg 8, Allée Gaspard Monge, Strasbourg 67000, France Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH- 1015 Lausanne, Switzerland Max Planck institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany BASF SE, GKS/E-B001, D-67056 Ludwigshafen, Germany Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland su: Surface chemistry Polymers Scanning tunneling microscopy X-ray photoelectron spectroscopy Density functionals Surface active agents sug: subj: Surface chemistry Polymers Scanning tunneling microscopy X-ray photoelectron spectroscopy Density functionals Surface active agents ab: We report on a combined scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) study on the surface-assisted assembly of the hexaiodo-substituted macrocycle cyclohexa-m-phenylene (CHP) toward covalently bonded polyphenylene networks on Cu(111), Au(111), and Ag(111) surfaces. STM and XPS indicate room temperature dehalogenation of CHP on either surface, leading to surface-stabilized CHP radicals (CHPR5) and coadsorbed iodine. Subsequent covalent intermolecular bond formation between CHPRs is thermally activated and is found to proceed at different temperatures on the three coinage metals. The resulting polyphenylene networks differ significantly in morphology on the three substrates: On Cu, the networks are dominated by "open" branched structures, on the Au surface a mixture of branched and small domains of compact network clusters are observed, and highly ordered and dense polyphenylene networks form on the Ag surface. Ab initio OFT calculations allow one to elucidate the diffusion and coupling mechanisms of CHPRs on the Cu(1 11) and Ag(1 11) surfaces. On Cu, the energy barrier for diffusion is significantly higher than the one for covalent intermolecular bond formation, whereas on Ag the reverse relation holds. By using a Monte Carlo simulation, we show that different balances between diffusion and intermolecular coupling determine the observed branched and compact polyphenylene networks on the Cu and Ag surface, respectively, demonstrating that the choice of the substrate plays a crucial role in the formation of two-dimensional polymers. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2010 holdings: @attributes: islocal: N |
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