Two-Dimensional One-Atom-Thick Gold Grown on Defect-Engineered Graphene

Author(s)
Wael Joudi, Sadegh Ghaderzadeh, Alberto Trentino, Kenichiro Mizohata, Kimmo Mustonen, Elena Besley, Jani Kotakoski, E. Harriet Åhlgren
Abstract

In this work, a general route to creating two-dimensional, one-atom-thick metal layers, metallene, on functionalized graphene is proposed. To explore its viability, low-energy ion irradiation is performed to introduce vacancies into initially pristine graphene, followed by ultralow-energy gold irradiation to deposit individual gold atoms onto it. While gold freely migrates on pristine graphene, vacancies provide anchoring points where gold atoms gather and promote the growth of atomically thin nanoplatelets. The physical and chemical structure of the gold flakes is confirmed through atomic-resolution scanning transmission electron microscopy and electron energy loss spectroscopy, while their formation is investigated using ab initio simulations. The thickness and diameter of the gold flakes are directly proportional to gold ion fluence during ultralow-energy ion irradiation. Gold atoms in small gold structures are arranged in a one-atom-thick hexagonal lattice. Larger goldene platelets with lateral sizes in the range of tens of nanometers contain multiple gold layers. Mono- and few-layer flakes are metastable under continuous 60 keV electron irradiation during imaging but occasionally rotate and take small jumps as the atoms at the edges move. A reversible transformation between a flat monolayer and an amorphous three-dimensional gold cluster is observed in the experiments and is also seen in the simulations.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
University of Nottingham, University of Helsinki
Journal
ACS Nano
Volume
19
Pages
22032–22043
No. of pages
12
ISSN
1936-0851
DOI
https://doi.org/10.1021/acsnano.5c01538
Publication date
06-2025
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics
Keywords
ASJC Scopus subject areas
General Materials Science, General Engineering, General Physics and Astronomy
Portal url
https://ucrisportal.univie.ac.at/en/publications/40a3b131-54ed-40e9-988a-5f6ae9d5caa2