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arXiv · 1707.04396

Magic Graphene Clusters Formation in the graphene CVD growth process on Ru and Rh

Junfeng Gao·Feng Ding
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Abstract

To improve atomically controlled chemical vapor deposition (CVD) growth of graphene, understanding the evolution from various carbon species to a graphene nuclei on various catalyst surfaces is essential. Experimentally, an ultra-stable carbon cluster on Ru(0001), Rh(111) surfaces was observed, while its structure and formation process were still under highly debate. Using ab initio calculations and kinetic analyses, we disclosed a specific type of carbon clusters, composed of a C21 core and a few dangling C atoms around, were exceptional stable in the size range from 21 to 27. The most stable one of them, an isomer of C24 characterized as three dangling C atoms attached to the C21 (denoted as C21-3C), is the most promising candidate for the experimental observation. The ultra-stability of C21-3C originates from both the stable core and the appropriate passivation of dangling carbon atoms by the catalyst surface.

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Junfeng Gao, Feng Ding. 2017-07-14. Magic Graphene Clusters Formation in the graphene CVD growth process on Ru and Rh. https://doi.org/10.1002/anie.201406570

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