Magic Carbon Clusters in the Chemical Vapor Deposition Growth of Graphene

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• 作者：Qinghong Yuan ; Junfeng Gao ; Haibo Shu ; Jijun Zhao ; Xiaoshuang Chen ; Feng Ding
• 刊名：The Journal of the American Chemical Society
• 出版年：2012
• 出版时间：February 15, 2012
• 年：2012
• 卷：134
• 期：6
• 页码：2970-2975
• 全文大小：942K
• 年卷期：v.134,no.6(February 15, 2012)
• ISSN：1520-5126

文摘

Ground-state structures of supported C clusters, C_N (N = 16, ..., 26), on four selected transition metal surfaces [Rh(111), Ru(0001), Ni(111), and Cu(111)] are systematically explored by ab initio calculations. It is found that the core鈥搒hell structured C₂₁, which is a fraction of C₆₀ possessing three isolated pentagons and C_3v symmetry, is a very stable magic cluster on all these metal surfaces. Comparison with experimental scanning tunneling microscopy images, dI/dV curves, and cluster heights proves that C₂₁ is the experimentally observed dominating C precursor in graphene chemical vapor deposition (CVD) growth. The exceptional stability of the C₂₁ cluster is attributed to its high symmetry, core鈥搒hell geometry, and strong binding between edge C atoms and the metal surfaces. Besides, the high barrier of two C₂₁ clusters鈥?dimerization explains its temperature-dependent behavior in graphene CVD growth.