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Exfoliation of natural van der Waals heterostructures to a single unit cell thickness

Lookup NU author(s): Dr Aleksey KozikovORCiD



This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


Weak interlayer interactions in van der Waals crystals facilitate their mechanical exfoliation to monolayer and few-layer two-dimensional materials, which often exhibit striking physical phenomena absent in their bulk form. Here we utilize mechanical exfoliation to produce a two-dimensional form of a mineral franckeite and show that the phase segregation of chemical species into discrete layers at the sub-nanometre scale facilitates franckeite’s layered structure and basal cleavage down to a single unit cell thickness. This behaviour is likely to be common in a wider family of complex minerals and could be exploited for a single-step synthesis of van der Waals heterostructures, as an alternative to artificial stacking of individual two-dimensional crystals. We demonstrate p-type electrical conductivity and remarkable electrochemical properties of the exfoliated crystals, showing promise for a range of applications, and use the density functional theory calculations of franckeite’s electronic band structure to rationalize the experimental results.

Publication metadata

Author(s): Velicky M, Toth P, Rakowski A, Rooney A, Kozikov A, Woods C, Mishchenko A, Fumagalli L, Yin J, Zolyomi V, Georgiou T, Haigh S, Novoselov K, Dryfe R

Publication type: Article

Publication status: Published

Journal: Nature Communications

Year: 2017

Volume: 8

Online publication date: 13/02/2017

Acceptance date: 24/12/2016

Date deposited: 03/07/2020

ISSN (electronic): 2041-1723

Publisher: Nature Publishing Group


DOI: 10.1038/ncomms14410


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