| AVS 66th International Symposium & Exhibition | |
| 2D Materials | Monday Sessions |
| Session 2D+AP+EM+MI+MN+NS+PS+TF-MoA |
| Session: | Nanostructures including Heterostructures and Patterning of 2D Materials |
| Presenter: | Mark Haastrup, Aarhus University, Denmark |
| Authors: | M.J. Haastrup, Aarhus University, Denmark M. Mammen, Aarhus University, Denmark J. Rodríguez-Fernández, Aarhus University, Denmark J.V. Lauritsen, Aarhus University, Denmark |
| Correspondent: | Click to Email |
2D materials exhibiting unique material properties have the potential for a huge impact on our future. Graphene, as the first discovered truly 2D material, has been extensively studied. However, the lack of an intrinsic band gap makes it inadequate for electronic and optical devices. MoS2 from the family of transition metal dichalcogenides has been intensively investigated for its possibility to be used in future applications. The vision is to integrate various 2D materials to realise an actual device. However, the actual assembly of these materials with high controllability remains a challenge. Vertical heterostructures, supported by Van der Waals interactions, have already been realised by manually stacking 2D materials on top of each other[1]. An ultimate thin device can be realised by creating lateral heterostructures with atomically sharp interfaces where each material is directly bonded to another. Currently, methods for in-plane bonding of MoS2 to other materials (e.g. graphene) are limited due to poor structural match. One possible solution is to develop selective bottom-up methods for synthesis of molecular nanostructures by self-assembly.
This study aim to investigate the fundamental nature of bonding of graphene nanoribbons (GNRs) to the edges of MoS2 nanoparticles by scanning tunnelling microscopy (STM). The aim is to synthesise GNRs from precursor molecules through a thermally activated Ullmann reaction already used elsewhere[2,3]. After initial growth of MoS2, it is necessary to anneal in a hydrogen atmosphere to activate the edges to facilitate the attachment of an intermediate structure of poly(para-phenylene) (PPP) wires. STM reveals the PPP wires have an affinity for the corners of the MoS2 nanoparticles with a distance, obtained from line scans across the adsorption site, consistent with a covalent C-S bond.
[1]: Pant et al., Nanoscale, 2016, 8, 7, 3870-3887
[2]: Cai et al., Nature, 2010, 466, 7305, 470–473
[3]: Basagni et al., J. Am. Chem. Soc., 2015, 137, 5, 1802-1808