Covalent Bonding in Surface-Confined Ullmann Polymerization
 |
Surface polymerization is of great interest as it enables the realization of graphene-like layers with tunable properties by simply modifying the architecture of the molecular building blocks used as precursors. We focus on some open points concerning the fundamentals of surface-catalyzed dehalogenative polymerization based on Ullmann coupling, widely used over the past decade to obtain 1D and 2D polymers on surfaces. M. Di Giovannantonio et al. ACS Nano 7 (9), 8190 (2013) http://pubs.acs.org/doi/abs/10.1021/nn4035684 |
| 1,4-dibromobenzene molecules were used as precursors, forming poly(para-phenylene) polymers by Ullmann coupling on Cu(110). Chemically sensitive techniques such as x-ray photoelectron spectroscopy (XPS) and near-edge x-ray absorption fine structure (NEXAFS) spectroscopy allow to unequivocally identify the existence of an organometallic intermediate product of reaction and the of a final extended conjugated structure. Scanning tunneling microscopy (STM), low energy electron diffraction (LEED) and first-principles calculations provide a deeper insight into the intermediate organometallic phase and on the fundamental role of the halogen in stabilizing specific structures. Fast-XPS analysis of the system during the transformation from organometallic chains to polymers unveils the exact transition temperature for this process. |
Retrieve article
Insight into Organometallic Intermediate and Its Evolution to Covalent Bonding in Surface-Confined Ullmann Polymerization, Marco Di Giovannantonio, Mohamed El Garah, Josh Lipton-Duffin, Vincent Meunier, Luis Cardenas, Yannick Fagot Revurat, Albano Cossaro, Alberto Verdini, Dmitrii F. Perepichka, Federico Rosei and Giorgio Contini. ACS Nano 2013, 7 (9), pp 8190-8198 DOI: 10.1021/nn4035684 http://pubs.acs.org/doi/abs/10.1021/nn4035684 |
|
Ultima modifica il Martedì, 17 Dicembre 2013 16:03
  |
Elettra-Sincrotrone Trieste S.C.p.A. di interesse nazionale
Strada Statale 14 - km 163,5 in AREA Science Park 34149 Basovizza, Trieste ITALY Tel. +39 040 37581 - Fax. +39 040 9380902 Anagrafe Nazionale Ricerche Cod. 51779CRP partita IVA 00697920320 |