In the past decade, on-surface synthesis on metallic substrates revealed many novel carbon materials with atomically precise structures and intriguing electronic properties. The on-surface coupling reactions take advantage of the catalytic properties of metal surfaces. Thereby, the construction of high-quality low-dimensional carbon nanostructures requires steering the reaction pathway by a clever precursor design and applying substrate templating effects. One of the challenges is the fabrication of long-range ordered two-dimensional covalent organic frameworks (2D COFs) via on-surface reactions in ultra-high vacuum due to the irreversible structure formation. Another essential aspect is preserving the intriguing electronic properties of 2D COFs using advanced physical and electronic decoupling schemes.
Figure: Macrocyle with full arm-chair edge, porous CNR, honeycomb 2D COF, honeycomb 2D MOF.
We aim to unravel the structural and electronic properties of novel topological and heteroatom doped graphene nanoribbons (GNRs) and 2D Dirac metal-organic frameworks (MOFs) and COFs fabricated by on-surface synthesis using high-resolution scanning probe microscopy/spectroscopy (STM,nc-AFM, and STS) at low temperatures.
Thesis topic: Topological GNRs: On-surface synthesis and electronic structure
We will study the on-surface synthesis of novel 1D GNRs and 2D Dirac materials on metal surfaces. Using high-resolution scanning probe microscopy/spectroscopy, we aim to understand the effect of heteroatom-doping and incorporation of non-six-membered rings on the electronic structure.
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