ACS Nano. 2013 Sep 24;7(9):8190-8. doi: 10.1021/nn4035684. Epub 2013 Sep 09.

Insight into organometallic intermediate and its evolution to covalent bonding in surface-confined ullmann polymerization.

ACS nano

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, Giorgio Contini

PMID: 23987501 DOI: 10.1021/nn4035684

Abstract

We provide insight into surface-catalyzed dehalogenative polymerization, analyzing the organometallic intermediate and its evolution into planar polymeric structures. A combined study using scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), low energy electron diffraction (LEED), near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and first-principles calculations unveils the structural conformation of substrate-bound phenylene intermediates generated from 1,4-dibromobenzene precursors on Cu(110), showing the stabilizing role of the halogen. The appearance of covalently bonded conjugated structures is followed in real time by fast-XPS measurements (with an acquisition time of 2 s per spectrum and heating rate of 2 K/s), showing that the detaching of phenylene units from the copper substrate and subsequent polymerization occur upon annealing above 460 ± 10 K.

Publication Types

• Journal Article
• Research Support, Non-U.S. Gov't
• Research Support, U.S. Gov't, Non-P.H.S.