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Updated: Jun 14, 2025
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Modulating the bandgap of Cr-intercalated bilayer graphene via combining the 18-electron rule and the 2D
Dan Li1, Zaijun Gui1, Mengxuan Ling1
1Department of Chemistry, Anhui University, Hefei, 230601, P. R. China. qinqinyuan@ahu.edu.cn.
Abstract:
Bandgap engineering of graphene is of great significance for its potential applications in electronic devices. Herein, we used a sandwich compound Cr(C6H6)2 as the building block to construct Cr-intercalated bilayer graphene (BLG), namely a C12Cr monolayer. Chemical bonding analysis reveals that strong d-π interaction ensures π electrons of the graphene layers and d orbitals of the Cr atoms localized in C6CrC6 units to achieve the favored 18-electron rule, thus leading to a bandgap of 0.24 eV. Subsequently, a C48Cr monolayer with lower proportion of Cr is further designed using Cr(C54H18)2 as building units, where a newly developed two-dimensional (2D) superatomic-molecule theory is introduced to rationalize its electronic structure. The C48Cr monolayer not only satisfies the 18-electron rule, but also localizes extra π electrons to form two layers of 2D superatomic crystals composed of 2D superatoms (◊O and ◊N), resulting in a wider bandgap of 0.74 eV. This work opens an effective avenue to modulate the bandgap of BLG via combining the 18-electron rule and the 2D superatomic-molecule theory.
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