Highly stable two-dimensional metal-carbon monolayer with interpenetrating honeycomb structures

Shulong Li,Na Guo,Chun Zhang,Yong Zhao,Kah-Meng Yam

doi:10.1038/s41699-021-00235-y

Abstract

With the ongoing effort in proposing and realizing functional two-dimensional (2D) materials, we predict by first-principles calculations a family of 2D metal-carbon (M–C) crystals consisting of M–C trigonal lattice interpenetrated with the metal buckled honeycomb structure. We suggest by simulations that the 2D M–C crystals can be readily fabricated by a self-organizing lattice reconstruction process after placing metal atoms on hollow sites of γ-graphyne. In total, we found 12 members of the family and they exhibit a variety of electronic and magnetic properties. In this work, we highlight and focus on the Fe member of the family, 2D-Fe2C12. Each Fe in 2D-Fe2C12 has a magnetic moment of 1 μB due to the spin splitting of Fe E1 bands at Fermi surface, resulting in half metallicity and high catalytic activity with unusually high-density single-atom Fe active sites. Ab initio molecular dynamics simulations revealed that the 2D-Fe2C12 retains its structural integrity up to 700 K of simulated short duration annealing. We expect these results to stimulate experimental research for the 2D M–C crystals we proposed.

Highlights

Since the rise of graphene[1,2], two-dimensional (2D) materials have attracted enormous interest in recent years owing to their unique properties and great potential in various applications
The reason behind the stability of such systems is owing to the presence of N atoms that form strong bonds with C atom and interact favorably with metal atoms in porphyrin and phthalocyanine
The conception of such material design is built upon the basis that graphyne (GY), a family of allotropes of 2D carbon consisting of a mixture of sp- and sp2-hybridized C atoms, offers various degrees of porosity27,28. γ-GY has been successfully synthesized via various bottom–up approaches[27,29]

Summary

Introduction

Since the rise of graphene[1,2], two-dimensional (2D) materials have attracted enormous interest in recent years owing to their unique properties and great potential in various applications. These materials exhibit very different electronic properties evident from the band structure of each system shown, in which 2D-Ti2C12 is a nonmagnetic metal, 2DRh2C12 is a nonmagnetic semiconductor with a direct bandgap of 0.45 eV at M point, 2D-Ru2C12 is a magnetic metal with a 0.31 μB of magnetic moment on each Ru atom, and 2D-Fe2C12 is half metal with a semiconducting spin-up channel of quasi bandgap 0.30 eV at M point, and ~1 μB of magnetic moment resides on each Fe atom.

Results

Conclusion