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arXiv · 2007.01291

Free-standing 2D metals from binary metal alloys

Janne Nevalaita·Pekka Koskinen
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Abstract

Recent experiment demonstrated the formation of free-standing Au monolayers by exposing Au-Ag alloy to electron beam irradiation. Inspired by this discovery, we used semi-empirical effective medium theory simulations to investigate monolayer formation in 30 different binary metal alloys composed of late d-series metals Ni, Cu, Pd, Ag, Pt, and Au. In qualitative agreement with the experiment, we find that the beam energy required to dealloy Ag atoms from Au-Ag alloy is smaller than the energy required to break the dealloyed Au monolayer. Our simulations suggest that similar method could also be used to form Au monolayers from Au-Cu alloy and Pt monolayers from Pt-Cu, Pt-Ni, and Pt-Pd alloys.

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Janne Nevalaita, Pekka Koskinen. 2020-07-02. Free-standing 2D metals from binary metal alloys. https://doi.org/10.1063/5.0010884

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