A mechanically and electronically robust graphene-based molecular junction

A molecular device, which is both mechanically and electronically stable under operating conditions at room temperature has recently been developed. In the report in Nature Nanotechnology, researchers from Switzerland, the Netherlands, the UK, and Israel describe how the anchoring of the transport molecules directly to the surface ensures mechanical stability. Concurrently, electronic stability is achieved by tweaking the electronic structure of the molecule junction to increase the electronic overlap with the graphene electrodes.

The geometry of the molecules between the graphene electrodes were sampled with ReaxFF molecular dynamics simulations.

DFT calculations helped to understand and predict the geometrical and electronic features of the molecules. Transmission calculations gave insight in the molecular transport mechanisms, establishing the crucial role of the π−π-stacked head groups for effective charge transport.

The experiments and calculations pave the way for further incorporating molecule-based functions into stable nanoelectronic systems in the future.

Molecular Electronics with graphene electrodes
A stable molecular bridge: the molecules in the junction are tethered to the SiO2 surface, rather than attached to the graphene electrodes (attached to gold electrodes)

M. El Abbasi et al., Robust graphene-based molecular devices, Nature Nanotechnology, 14, 957-961 (2019)

Key concepts