Villalpando Graciela, Xie Jiaze, Mathur Nitish, Cheng Guangming, Yao Nan, Schoop Leslie M
Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
Princeton Materials Institute, Princeton, NJ 08544, USA.
Nanoscale Horiz. 2024 Sep 23;9(10):1766-1773. doi: 10.1039/d4nh00137k.
Magnetic two-dimensional (2D) materials are a unique class of quantum materials that can exhibit interesting magnetic phenomena, such as layer-dependent magnetism. The most significant barrier to 2D magnet discovery and study lies in our ability to exfoliate materials down to the monolayer limit. Therefore designing exfoliation methods that produce clean, monolayer sheets is crucial for the growth of 2D material research. In this work, we develop a facile chemical exfoliation method using lithium naphthalenide for obtaining 2D nanosheets of magnetic van der Waals material CrOCl. Using our optimized method, we obtain freestanding monolayers of CrOCl, with the thinnest measured height to date. We also provide magnetic characterization of bulk, intercalated intermediate, and nanosheet pellet CrOCl, showing that exfoliated nanosheets of CrOCl exhibit magnetic order. The results of this study highlight the tunability of the chemical exfoliation method, along with providing a simple method for obtaining 2D CrOCl.
磁性二维（2D）材料是一类独特的量子材料，能够展现出有趣的磁现象，比如层依赖磁性。二维磁体发现和研究的最大障碍在于我们将材料剥离至单层极限的能力。因此，设计能够产生洁净单层薄片的剥离方法对于二维材料研究的发展至关重要。在这项工作中，我们开发了一种使用萘锂的简便化学剥离方法，用于获得磁性范德华材料CrOCl的二维纳米片。通过我们优化后的方法，我们获得了迄今为止测量高度最薄的独立CrOCl单层。我们还提供了块状、插层中间体和纳米片颗粒CrOCl的磁性表征，表明剥离后的CrOCl纳米片呈现出磁有序。这项研究的结果突出了化学剥离方法的可调性，同时提供了一种获得二维CrOCl的简单方法。
