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

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 gamma-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 mu(B) 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.

Automated summary

This study predicts a family of 2D metal-carbon crystals through first-principles calculations, suggests their easy fabrication through self-organizing lattice reconstruction, and highlights their unique electronic and magnetic properties.