Remarkably high tensile strength and lattice thermal conductivity in wide band gap oxidized holey graphene CO nanosheet.

Recently, the synthesis of oxidized holey graphene with the chemical formula CO has been reported (J. Am. Chem. Soc. 2024, 146, 4532). We herein employed a combination of density functional theory (DFT) and machine learning interatomic potential (MLIP) calculations to investigate the electronic, optical, mechanical and thermal properties of the CO monolayer, and compared our findings with those of its CN counterpart. Our analysis shows that while the CN monolayer exhibits delocalized π-conjugation and shows a 2.47 eV direct-gap semiconducting behavior, the CO counterpart exhibits an indirect gap of 3.47 eV. We found that while the CN monolayer exhibits strong absorption in the visible spectrum, the initial absorption peaks in the CO lattice occur at around 5 eV, falling within the UV spectrum. Notably, we found that the CO nanosheet presents significantly higher tensile strength compared to its CN counterpart. MLIP-based calculations show that at room temperature, the CO nanosheet can exhibit remarkably high tensile strength and lattice thermal conductivity of 42 GPa and 129 W/mK, respectively. The combined insights from DFT and MLIP-based results provide a comprehensive understanding of the electronic and optical properties of CO nanosheets, suggesting them as mechanically robust and highly thermally conductive wide bandgap semiconductors.