Remarkably high tensile strength and lattice thermal conductivity in wide band gap oxidized holey graphene C2O nanosheet
Fazel Shojaei, Qinghua Zhang, Xiaoying Zhuang, Bohayra Mortazavi
Abstract
Abstract Recently, the synthesis of oxidized holey graphene with the chemical formula C 2 O 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 C 2 O monolayer, and compared our findings with those of its C 2 N counterpart. Our analysis shows that while the C 2 N monolayer exhibits delocalized π-conjugation and shows a 2.47 eV direct-gap semiconducting behavior, the C 2 O counterpart exhibits an indirect gap of 3.47 eV. We found that while the C 2 N monolayer exhibits strong absorption in the visible spectrum, the initial absorption peaks in the C 2 O lattice occur at around 5 eV, falling within the UV spectrum. Notably, we found that the C 2 O nanosheet presents significantly higher tensile strength compared to its C 2 N counterpart. MLIP-based calculations show that at room temperature, the C 2 O 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 C 2 O nanosheets, suggesting them as mechanically robust and highly thermally conductive wide bandgap semiconductors.