Bukvišová Kristýna, Kalousek Radek, Patočka Marek, Zlámal Jakub, Planer Jakub, Mahel Vojtěch, Citterberg Daniel, Novák Libor, Šikola Tomáš, Kodambaka Suneel, Kolíbal Miroslav
CEITEC BUT, Brno University of Technology, Purkyňova 123, 612 00 Brno, Czech Republic.
Thermo Fisher Scientific, Vlastimila Pecha 12, 627 00 Brno, Czech Republic.
J Phys Chem Lett. 2025 Sep 25;16(38):10020-10026. doi: 10.1021/acs.jpclett.5c02321. Epub 2025 Sep 17.
Rheotaxy─growth of crystalline layers on molten surfaces─is considered as a promising approach for achieving large-scale monolayers of two-dimensional (2D) materials via seamless stitching of 2D domains during growth on molten metals. However, the mechanisms leading to this process are not well understood. Here, we present in situ microscopic observations of rheotaxy of graphene via chemical vapor deposition on molten gold and copper. We show that the graphene domains undergo translational and rotational motions, leading to self-assembly, during growth on molten metals. Using environmental and ultrahigh vacuum scanning electron microscopy and high-temperature (∼1300 K) atomic force microscopy, coupled with density functional theory and continuum modeling, we suggest that the observed graphene domain dynamics is due to forces arising from capillary waves on the surface of the liquid metal. Our results provide new insights into the mechanisms leading to self-assembly during rheotaxy of 2D layers.
流变排列——在熔融表面上生长晶体层——被认为是一种很有前景的方法，可通过在熔融金属上生长过程中二维（2D）畴的无缝拼接来实现二维材料的大规模单层。然而，导致这一过程的机制尚未得到很好的理解。在此，我们展示了通过化学气相沉积在熔融金和铜上对石墨烯流变排列的原位微观观察。我们表明，石墨烯畴在熔融金属上生长期间会经历平移和旋转运动，从而导致自组装。利用环境和超高真空扫描电子显微镜以及高温（约1300K）原子力显微镜，结合密度泛函理论和连续介质模型，我们认为观察到的石墨烯畴动力学是由液态金属表面的毛细波产生的力引起的。我们的结果为二维层流变排列过程中导致自组装的机制提供了新的见解。
