Interactions between C and Cu atoms in single-layer graphene: direct observation and modeling

Emi Kano, Ayako Hashimoto , Tomoaki Kaneko, Nobuo Tajima, Takahisa Ohno, and Masaki Takeguchi, 2016
Fusion TEM holder tip
Image courtesy of Nanoscale

Abstract

Metal doping into the graphene lattice has been studied recently to develop novel nanoelectronic devices and to gain an understanding of the catalytic activities of metals in nanocarbon structures. Here we report the direct observation of interactions between Cu atoms and single-layer graphene by transmission electron microscopy. We document stable configurations of Cu atoms in the graphene sheet and unique transformations of graphene promoted by Cu atoms. First-principles calculations based on density functional theory reveal a reduction of energy barrier that caused rotation of C–C bonds near Cu atoms. We discuss two driving forces, electron irradiation and in situ heating, and conclude that the observed transformations were mainly promoted by electron irradiation. Our results suggest that individual Cu atoms can promote reconstruction of single-layer graphene.

Impact Statement

The authors report the direct observation of interactions between Cu atoms and single-layer graphene. Two driving forces are considered: electron irradiation and in situ heating. It is concluded that the observed transformations were mainly promoted by electron irradiation.