Dirac Semimetals in Homogeneous Holey Carbon Nitride Monolayers

Abstract

In this work, we propose four novel holey carbon nitride monolayer C7N3, C10N3, C13N3, and C19N3 stoichiometries intriguingly behaving as ideal 2D Dirac semimetals whose Dirac cones are rightly located at the Fermi level. Moreover, the results of Gibbs free energies, phonon dispersions, ab initio molecular dynamics, and linear elastic constants indicate that their stabilities are comparable with the already-synthesized 2D carbon nitride materials. The Dirac cones of the systems originate from the hopping between all p z orbitals of the C and N atoms. The theory of elementary band representation indicates that the Dirac cones of the systems come from the time-reversal forced twofold degeneracy at K and K′ points. Furthermore, we find that the Dirac cones of the systems are robust against the spin–orbit coupling and external strain. Considering their excellent conductivity as Dirac semimetals, the four holey carbon nitride monolayers are potential candidates for the applications in future high-performance electronic devices.

2D Homogeneous Holey Carbon Nitride: An Efficient Anode Material for Li‐ion Batteries With Ultrahigh Capacity

“…Recently, Tan et al have theoretically designed C x N 3 (x = 7, 10, 14, 19) monolayers with excellent logistics and proposed all possible synthetic routes for experimental fabrication. Taking inspiration from their work, we have successfully reproduced the geometries proposed by Tan et al [22] These four monolayers are found to have similar physical properties as well as almost same level of thermodynamic stability. Thus, we have decided to analyze one small and one large system to find the electrochemical performance.…”

“…In this circumstances, it is interesting to explore the electrochemical performance along with the electrode utility of these newly designed carbon nitride (C x N 3 ; x = 10, 19) monolayers having perfectly planar porous geometry with Dirac semimetallicity in their electronic structure. [22] In order to have clear understanding of the electrochemical performance of newly designed C x N 3 monolayers, herein we have performed first-principles density functional theory (DFT) calculations to predict the potential of C x N 3 monolayers as anode material in LIBs. In this article, employing simple thermodynamic treatment we have re-optimized the C x N 3 monolayers and checked their thermal stability using ab-initio molecular dynamics simulation (AIMD) at 500 K for 5 ps with a time step of 1 fs.…”

Two-dimensional semiconductor materials with high stability and electron mobility in group-11 chalcogenide compounds: MNX (M = Cu, Ag, Au; N = Cu, Ag, Au; X = S, Se, Te; M ≠ N)

“…In order to manufacture high-performance miniaturized devices, such as ultrathin channel field-effect transistors 2,3 (FETs), suitable band gaps, high carrier mobility and high stability are essential for 2D materials. [4][5][6][7][8][9] So far, graphene, 1 black phosphorene and two-dimensional transition metal dichalcogenides (TMDs) have received extensive research attention due to their excellent electronic properties. Graphene's two-dimensional planar structure and ultra-high carrier mobility make it very promising in the field of field-effect transistors.…”

Highly Polymerized Wine-Red Carbon Nitride to Enhance Photoelectrochemical Water Splitting Performance of Hematite

“…Supramolecular precursors can be fabricated by the self-assembly of melamine, urea, barbituric acid, etc., by utilizing the hydrogen bonding and π–π interaction between these C,N-containing monomers. − The C/N ratio of carbon nitride can be conveniently adjusted by selecting carbon- or nitrogen-rich monomers for supramolecular precursors, which strongly influences the electronic structure, band gap, and band edges position of the obtained carbon nitride …”

“…17−19 The C/N ratio of carbon nitride can be conveniently adjusted by selecting carbon-or nitrogen-rich monomers for supramolecular precursors, which strongly influences the electronic structure, band gap, and band edges position of the obtained carbon nitride. 20 To achieve both high polymerization degree and optimum band structures of carbon nitride, the integration of ionothermal technology and supramolecular precursors seems to be promising, which, however, has never been reported to our knowledge. Addressing this, a supramolecular precursor CMBA was first synthesized through the molecular-level selfassembly of barbituric acid, melamine, and cyanuric acid, which was then ionothermally converted into a unique winered carbon nitride (WRCN) in the presence of salts (NaCl, KCl) under high temperature.…”