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DOE OSTI · 1802417

Dynamics of graphene/Al interfaces using COMB3 potentials

Abstract

This paper describes the development of a third-generation charge optimized many-body (COMB3) potential for Al-C and its application to the investigation of aluminum/graphene nanostructures. In particular, the new COMB3 potential was used to investigate the interactions of aluminum surfaces with pristine and defective graphene sheets. Classical molecular dynamics simulations were performed at temperatures of 300–900 K to investigate the structural evolution of these interfaces. In this work, the results indicate that, although the interfaces between Al and graphene are mostly weakly bonded, aluminum carbide can form under the right conditions, including the presence of vacancy defects in graphene, undercoordinated Al in surface regions with sharp boundaries, and at high temperatures. COMB3 potentials were further used to examine a new method to transfer graphene between Al surfaces as well as between Al and Cu surfaces by controlling the angle of graphene between the two surfaces. The findings indicate that, by controlling the peeling angles, it is possible to transfer graphene without any damage from the surface having greater graphene/surface adhesion to another surface with less adhesion.

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Zhang, Difan, Fonseca, Alexandre F., Liang, Tao, Phillpot, Simon R., Sinnott, Susan B.. 2019-11-27. Dynamics of graphene/Al interfaces using COMB3 potentials. https://doi.org/10.1103/physrevmaterials.3.114002

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36 MATERIALS SCIENCE↗