Two-dimensional porous graphitic carbon nitride C6N7 monolayer: First-principles calculations

Abstract

The fabrication of the C6N7 monolayer [Zhao et al., Sci. Bull. 66, 1764 (2021)] motivated us to discover the optical, structural, mechanical, and electronic properties of the C6N7 monolayer by employing the density functional theory (DFT) method. We find that the shear modulus and Young's modulus of the C6N7 monolayer are smaller than the relevant values of graphene. However, Poisson's ratio is more significant than that of graphene. Applying the PBE (HSE06) functional bandgap of the C6N7 monolayer is 1.2 (1.97) eV, and the electronic dispersion is almost isotropic around the Γ point. C6N7 is more active in the ultraviolet region as compared to the visible light region. This study provides outstanding results, highlighting the bright viewpoints for the applications of the C6N7 monolayer in electronic and optical systems.

Erratum: “Two-dimensional porous graphitic carbon nitride C6N7 monolayer: First-principles calculations” [Appl. Phys. Lett. 119, 142102 (2021)]

“…As reported in Fig. 1e of our paper [12], ZA out-of-plane mode proves the existence of C13, C23, and C33.…”

Two‐Dimensional Dirac Nodal Line Carbon Nitride to Anchor Single‐Atom Catalyst for Oxygen Reduction Reaction

“…[12,13] Besides these porous 2DCN materials, pore-free honeycomb structure 2D C 3 N had been synthesized via direct pyrolysis, which is a semiconductor with an indirect bandgap ( � 0.39 eV). [14][15][16] In addition, a lot of 2DCN materials had also been predicted theoretically, such as C 3 N 2 , [17] C 3 N 3 , [18] C 4 N, [19] C 4 N 3 , [20] C 6 N, [21] C 6 N 7 , [22] and C 9 N 4 . [23] Nodal-line semimetal is a new state of quantum matter, in which the conduction and valence bands cross at the Fermi level and form a continuous Dirac loop.…”

“…Besides these porous 2DCN materials, pore‐free honeycomb structure 2D C 3 N had been synthesized via direct pyrolysis, which is a semiconductor with an indirect bandgap (≈0.39 eV) [14–16] . In addition, a lot of 2DCN materials had also been predicted theoretically, such as C 3 N 2 , [17] C 3 N 3 , [18] C 4 N, [19] C 4 N 3 , [20] C 6 N, [21] C 6 N 7 , [22] and C 9 N 4 [23] …”

Comment on Two-dimensional porous graphitic carbon nitride C6N7 monolayer: First-principles calculations [Appl. Phys. Lett. 2021, 119, 142102]

“…Bafekry et al 1 predicted the C11 = 258.6 GPa, C22 = 290.8 GPa, and C12 = 70.73 GPa and C13 = C23 = 2.49 GPa, C33 = 9.05 GPa, C44 = 25.86 GPa, C55 = 2.90 GPa, and C66 = 3.08 GPa for the C6N7 monolayer. An isolated layer that is in contact with vacuum on the both sides and is thus free to move toward the out-of-plane direction upon the geometry optimization, follow the plane-stress theory and cannot exhibit non-zero C13, C23, C33, C44 and C55 values.…”

“…An isolated layer that is in contact with vacuum on the both sides and is thus free to move toward the out-of-plane direction upon the geometry optimization, follow the plane-stress theory and cannot exhibit non-zero C13, C23, C33, C44 and C55 values. In contrast with basic physics, Bafekry and coworkers in their original work 2 and their recently published erratum . 1 , reported C13, C23, C33, C44 and C55 values for the C6N7 monolayer with two-decimal precisions.…”