Dierke Tobias, Wolff Stefan, Gillen Roland, Eisenkolb Jasmin, Nagel Tamara, Maier Sabine, Kivala Milan, Hauke Frank, Hirsch Andreas, Maultzsch Janina
Department of Physics, Chair of Experimental Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 7, 91058, Erlangen, Germany.
Department of Chemistry and Pharmacy, Chair of Organic Chemistry II & Center of Advanced Materials and Processes, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nikolaus-Fiebiger-Str. 10, 91058, Erlangen, Germany.
Angew Chem Int Ed Engl. 2025 Jan 10;64(2):e202414593. doi: 10.1002/anie.202414593. Epub 2024 Dec 12.
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° and 7° 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 moiré 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 moiré lattice in controlling the non-covalent functionalization of tBLG. Our approach can be generalized for designing nanoscale patterns on two-dimensional (2D) materials using moiré structures as a template. This could facilitate the fabrication of nanoscale devices with locally controlled varying chemical functionality.
我们提出了一种新颖的方法来实现扭曲双层石墨烯（tBLG）非共价功能化程度的空间变化。将扭曲角在约5°至7°之间变化的tBLG用1,4,5,8,9,11-六氮杂三亚苯六腈（HATCN）分子进行非共价功能化。我们的结果表明功能化程度与tBLG的扭曲角之间存在相关性。这种相关性是通过拉曼光谱确定的，其中与较小扭曲角区域相比，较大扭曲角区域的HATCN峰强度较低。我们认为，HATCN吸附遵循tBLG的莫尔图案，避开AA堆叠区域，主要附着在tBLG具有局部AB堆叠顺序的区域，形成整体的ABA堆叠构型。这得到了密度泛函理论（DFT）计算的支持。我们的工作突出了莫尔晶格在控制tBLG非共价功能化中的作用。我们的方法可以推广到以莫尔结构为模板在二维（2D）材料上设计纳米级图案。这可以促进具有局部可控变化化学功能的纳米级器件的制造。
