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

TL;DR

This paper uses first-principles DFT calculations to reassess the mechanical properties of the C6N7 monolayer, predicting a much higher elastic modulus and tensile strength than previous reports, indicating superior mechanical robustness.

Contribution

It provides new first-principles predictions of the elastic modulus and tensile strength of the C6N7 monolayer, challenging prior DFT results and highlighting its potential for mechanical applications.

Findings

Elastic modulus predicted as 267 GPa, much higher than previous 36.29 GPa.

Maximum tensile strength estimated at 20.5 GPa.

Reveals outstanding mechanical properties of the C6N7 monolayer.

Abstract

Recently, Bafekry et al. [Appl. Phys. Lett. 119, 142102 (2021)] reported their density functional theory (DFT) results on the elastic constants of a novel C6N7 monolayer. They predicted a very soft elastic modulus of 36.29 GPa for the C6N7 monolayer, which is remarkably low for carbon-nitride 2D lattices. Using DFT calculations, we predict a remarkably higher elastic modulus of 267 GPa for this monolayer. The maximum tensile strength is also predicted to be 20.5 GPa, revealing the outstanding mechanical properties of the C6N7 monolayer.