Moir\'e lattice of twisted bilayer graphene as template for non-covalent functionalization

Tobias Dierke; Stefan Wolff; Roland Gillen; Jasmin Eisenkolb; Tamara Nagel; Sabine Maier; Milan Kivala; Frank Hauke; Andreas Hirsch; Janina Maultzsch

arXiv · 2406.17573

Moir\'e lattice of twisted bilayer graphene as template for non-covalent functionalization

Tobias Dierke·Stefan Wolff·Roland Gillen·Jasmin Eisenkolb·Tamara Nagel·Sabine Maier·Milan Kivala·Frank Hauke·Andreas Hirsch·Janina Maultzsch

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Abstract

We present a novel approach to achieve spatial variations in the degree of non-covalent functionalization of twisted bilayer graphene (tBLG). The tBLG with twist angles varying between ~ 5{\deg} and 7{\deg} was non-covalently functionalized with 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile (HATCN) molecules. Our results show a correlation between the degree of functionalization and the twist angle of tBLG. This correlation was determined through Raman spectroscopy, where areas with larger twist angles exhibited a lower HATCN peak intensity compared to areas with smaller twist angles. We suggest that the HATCN adsorption follows the moir\'e pattern of tBLG by avoiding AA-stacked areas and attach predominantly to areas with a local AB-stacking order of tBLG, forming an overall ABA-stacking configuration. This is supported by density functional theory (DFT) calculations. Our work highlights the role of the moir\'e lattice in controlling the non-covalent functionalization of tBLG. Our approach can be generalized for designing nanoscale patterns on two-dimensional (2D) materials using moir\'e structures as a template.

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Tobias Dierke, Stefan Wolff, Roland Gillen, Jasmin Eisenkolb, Tamara Nagel, Sabine Maier, Milan Kivala, Frank Hauke, Andreas Hirsch, Janina Maultzsch. 2024-06-25. Moir\'e lattice of twisted bilayer graphene as template for non-covalent functionalization. https://arxiv.org/abs/2406.17573

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