| AVS 66th International Symposium & Exhibition | |
| Nanometer-scale Science and Technology Division | Wednesday Sessions |
| Session NS+2D+AS-WeA |
| Session: | Probing and Modifying Surface and Interfacial Chemistry at the Nanoscale |
| Presenter: | Sabine Maier, University of Erlangen-Nürnberg, Germany |
| Correspondent: | Click to Email |
On-surface synthesis has attracted significant attention in recent years due to its potential to fabricate novel low-dimensional nanomaterials with atomic precision. In order to understand and control the synthesis of high-quality low-dimensional nanostructures, many efforts have been made to steer the reaction pathway by the design of smart precursors and by applying templating effects from the substrate. One of the challenges is the fabrication of long-range ordered two-dimensional covalently-linked networks via on-surface reactions. In contrast to molecular self-assemblies that are constructed by non-covalent bonds, the irreversible nature of the covalent bonds limits the structural control, which results in small domains and defects.
In my presentation, I will focus on recent high-resolution scanning probe microscopy experiments in combination with density-functional theory about the bottom-up fabrication and electronic properties of atomically precise one- and two-dimensional molecular nanostructures on metals.[1-4] Thereby, the effect of the flexibility, the symmetry, and chirality of the precursor molecules on the structure formation of covalently-linked molecular structures will be discussed. In particular, I will outline how well-ordered nanoporous 1D and 2D covalent molecular structures can be fabricated by use of debromination coupling reactions. We demonstrate the narrowing of the electronic band gap by increasing the π-system in covalently-linked structures and also show delocalized electronic states in surface-supported organometallic networks. Finally, I will conclude with a comparison of the structure formation of molecular nanostructures on bulk insulators and metal surfaces.
[1] C. Steiner et al. Nature Communications, 2017, 8, 14765.
[2] M. Ammon, T. Sander, S. Maier, J. Am. Chem. Soc., 2017 139 (37), 12976–12984.
[3] Z. Yang et al. Nanoscale, 2018, 10, 3769-3776.
[4] X. Zhang et al., ACS Nano, 2019, 13 (2), 1385–1393.