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arXiv · 2202.04485

Indirect measurement of the carbon adatom migration barrier on graphene

Andreas Postl·Pit Pascal Patrick Hilgert·Alexander Markevich·Jacob Madsen·Kimmo Mustonen·Jani Kotakoski·Toma Susi
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Abstract

Although surface diffusion is critical for many physical and chemical processes, including the epitaxial growth of crystals and heterogeneous catalysis, it is particularly challenging to directly study. Here, we estimate the carbon adatom migration barrier on freestanding monolayer graphene by quantifying its temperature-dependent electron knock-on damage. Due to the fast healing of vacancies by diffusing adatoms, the damage rate decreases with increasing temperature. By analyzing the observed damage rates at 300-1073 K using a model describing our finite scanning probe, we find a barrier of (0.33 \pm 0.03) eV.

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Andreas Postl, Pit Pascal Patrick Hilgert, Alexander Markevich, Jacob Madsen, Kimmo Mustonen, Jani Kotakoski, Toma Susi. 2022-02-09. Indirect measurement of the carbon adatom migration barrier on graphene. https://doi.org/10.1016/j.carbon.2022.05.039

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