Dresden 2017 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 97: Nanostructures at Surfaces: Molecular Systems II
O 97.6: Vortrag
Donnerstag, 23. März 2017, 16:45–17:00, REC/PHY C213
Electronic structure of one- and two-dimensional polymers fabricated in a hierarchical on-surface synthesis on Au(111) — Christian Steiner1, Maximilian Ammon1, Zechao Yang1, Julian Gebhardt2, Alexander Heidenreich3, Natalie Hammer3, Andreas Görling2, Milan Kivala3, and •Sabine Maier1 — 1Department of Physics, University of Erlangen-Nürnberg, Erlangen, Germany — 2Chair of Theoretical Chemistry, Department of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Erlangen, Germany — 3Chair of Organic Chemistry I, Department of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Erlangen, Germany
The fabrication of nanostructures in a bottom-up approach from specific molecular precursors offers the opportunity to create tailored materials for applications in nanoelectronics. However, the formation of defect-free 2D covalent networks remains a challenge and makes it difficult to unveil their electronic structure.
Here, we report on the hierarchical on-surface synthesis of nearly defect-free 1D and 2D covalent architectures on Au(111), which were investigated by low-temperature scanning tunneling microscopy in combination with density-functional theory. The carbonyl-bridged triphenylamine precursors formed six-membered macrocycles and 1D chains as intermediates in a Ullmann-type coupling reaction that were subsequently interlinked to 2D networks. We observed a reduction of the electronic band gap from the monomer to the 1D and 2D structures. The significant drop of the gap from the monomer to the polymer confirms an effective conjugation along the building blocks.