Abstract
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 104 nm2 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.
Highlights
The rise of 2D materials made it possible to form heterostructures held together by weak interplanar van der Waals interactions
We demonstrate that a tunable periodic potential with 1D geometry on graphene can be realized at ambient conditions in a hybrid Van der Waals (vdW) heterostructure composed of a 2D supramolecular lattice (SL) self-assembled on graphene, with single domains extending over areas exceeding 250 Â 250 nm[2]
The analogy between hybrid and fully inorganic vdW heterostructures goes beyond their layered nature; in analogy to stacks of inorganic 2D materials, vdW forces drive the interaction between graphene and the self-assembled molecular layer, and similar inter-layer interactions can be envisaged
Summary
The rise of 2D materials made it possible to form heterostructures held together by weak interplanar van der Waals interactions. 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. From a more fundamental point of view, the mutual interaction between vertically-stacked 2D materials generates electronic properties that are different from those of the isolated materials, as experimentally demonstrated for graphene on boron nitride[9,10,11,12,13] In the latter case, a Moirepattern develops due to the lattice mismatch between the two materials[14], resulting in a periodic potential (superlattice) with hexagonal geometry capable of modifying profoundly the band structure of graphene. By using a photoreactive organic molecule, we show how a subtle photo-induced change in the chemical structure of the starting molecule leads to a different amplitude of the potential, while leaving the periodicity unaltered
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
