On‐Surface Synthesis of Nitrogen‐Doped Kagome Graphene

Abstract

Nitrogen‐doped Kagome graphene (N‐KG) has been theoretically predicted as a candidate for the emergence of a topological band gap as well as unconventional superconductivity. However, its physical realization still remains very elusive. Here, we report on a substrate‐assisted reaction on Ag(111) for the synthesis of two‐dimensional graphene sheets possessing a long‐range honeycomb Kagome lattice. Low‐temperature scanning tunneling microscopy (STM) and atomic force microscopy (AFM) with a CO‐terminated tip supported by density functional theory (DFT) are employed to scrutinize the structural and electronic properties of the N‐KG down to the atomic scale. We demonstrate its semiconducting character due to the nitrogen doping as well as the emergence of Kagome flat bands near the Fermi level which would open new routes towards the design of graphene‐based topological materials.

Carbon Kagome nanotubes—quasi-one-dimensional nanostructures with flat bands

“…We suggest two possibilities here, both based on the organic synthesis of Kagome graphene and subsequent roll-up of this material to form CKNTs. One possibility is to use silver adatoms to transform tetrabromobocyclopropene to intermediate organometallic complex and to then form Kagome graphene on the surface of SiO 2 substrate with etchant sensitive gold layer in between , 93 as represented in left panel of Fig. 19a.…”

“…Examples of successful synthesis of such unusual carbon allotropes include g-graphyne, [152][153][154][155] T-carbon 73,190 and nitrogen-doped Kagome graphene. 93,94 In particular, various methods of synthesis of conventional carbon nanotubes, including laser ablation and chemical vapor deposition have been explored. 191,192 Some of these techniques have also been successfully used in manufacturing other 1D carbon allotropes, e.g.…”

“…, nitrogen-doped graphene on a silver substrate—a 2D material with a Kagome pattern, has been carried out recently. 93,94 Moreover, synthesis of novel complex nanotube structures in general (see e.g. ref.…”

“…23,[87][88][89][90][91][92] Although Kagome graphene remains to be experimentally synthesized, successful synthesis of a variant of this material, i.e., nitrogen-doped graphene on a silver substrate-a 2D material with a Kagome pattern, has been carried out recently. 93,94 Moreover, synthesis of novel complex nanotube structures in general (see e.g. ref.…”