The most widespread method for the synthesis of 2D–2D heterostructures is the direct growth of one material on top of the other. Alternatively, flakes of different materials can be manually stacked on top of each other. Both methods typically involve stacking 2D layers through van der Waals forces—such that these materials are often referred to as van der Waals heterostructures—and are stacked one crystal or one device at a time. Here we describe the covalent grafting of 2H-MoS₂ flakes onto graphene monolayers embedded in field-effect transistors. A bifunctional molecule featuring a maleimide and a diazonium functional group was used, known to connect to sulfide- and carbon-based materials, respectively. MoS₂ flakes were exfoliated, functionalized by reaction with the maleimide moieties and then anchored to graphene by the diazonium groups. This approach enabled the simultaneous functionalization of several devices. The electronic properties of the resulting heterostructure are shown to be dominated by the MoS₂–graphene interface.

合成 2D-2D 异质结构最普遍的方法是在另一种材料上直接生长一种材料。或者，不同材料的薄片可以手动堆叠在一起。这两种方法通常都涉及通过范德华力堆叠二维层——因此这些材料通常被称为范德华异质结构——并且一次堆叠一个晶体或一个器件。在这里，我们描述了将 2H-MoS ₂薄片共价接枝到嵌入场效应晶体管中的石墨烯单层上。使用了具有马来酰亚胺和重氮官能团的双功能分子，已知它们分别连接到硫化物和碳基材料。_二硫化钼薄片被剥离，通过与马来酰亚胺部分的反应进行功能化，然后通过重氮基团锚定到石墨烯上。这种方法可以同时实现多个设备的功能化。所得异质结构的电子特性显示出由 MoS ₂ -石墨烯界面支配。