University of Strasbourg, CNRS, ISIS UMR 7006, 8 Allée Gaspard Monge, F-67000 Strasbourg, France.
Laboratory for Chemistry of Novel Materials, Center for Research in Molecular Electronics and Photonics, University of Mons, Place du Parc 20, 7000 Mons, Belgium.
Nat Commun. 2017 Mar 21;8:14767. doi: 10.1038/ncomms14767.
The rise of 2D materials made it possible to form heterostructures held together by weak interplanar van der Waals interactions. Within such van der Waals heterostructures, the occurrence of 2D periodic potentials significantly modifies the electronic structure of single sheets within the stack, therefore modulating the material properties. However, these periodic potentials are determined by the mechanical alignment of adjacent 2D materials, which is cumbersome and time-consuming. Here we show that programmable 1D periodic potentials extending over areas exceeding 10 nm and stable at ambient conditions arise when graphene is covered by a self-assembled supramolecular lattice. The amplitude and sign of the potential can be modified without altering its periodicity by employing photoreactive molecules or their reaction products. In this regard, the supramolecular lattice/graphene bilayer represents the hybrid analogue of fully inorganic van der Waals heterostructures, highlighting the rich prospects that molecular design offers to create ad hoc materials.
二维材料的兴起使得由弱层间范德华相互作用结合的异质结构得以形成。在这种范德华异质结构中，二维周期性势的出现显著地改变了堆叠中单张薄片的电子结构，从而调节了材料的性能。然而，这些周期性势是由相邻二维材料的机械排列决定的，这一过程既繁琐又耗时。在这里，我们展示了当石墨烯被自组装超分子格子覆盖时，会出现可扩展至超过 10nm 且在环境条件下稳定的可编程一维周期性势。通过使用光反应性分子或其反应产物，可以在不改变周期性的情况下，对势的幅度和符号进行修改。在这方面，超分子格子/石墨烯双层结构代表了完全无机范德华异质结构的混合模拟，突出了分子设计为创造特定材料所提供的丰富前景。
