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

Emi Kano, Ayako Hashimoto, Tomoaki Kaneko, Nobuo Tajima, Takahisa Ohno and Masaki Takeguchi, 2016

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

Interaction between Cu single atoms with carbon atoms of a sheet of graphene at 150C and 300C was studied. Through DFT calculations energy barriers for defect formation and c-c bond rotation were calculated and effect of e-beam irradiation was investigated as well.