Superior Adhesion of Monolayer Amorphous Carbon to Copper

Abstract The single‐atom thickness of graphene holds great potential for device scaling, but its effectiveness as a thin metal‐ion diffusion barrier in microelectronics and a corrosion barrier for plasmonic devices is compromised by weak van der Waals interactions with copper (Cu), leading to delamination issues. In contrast, monolayer amorphous carbon (MAC), a recently reported single‐atom‐thick carbon film with a disordered sp 2 hybridized structure, demonstrates superior adhesion properties. This study reveals that MAC exhibits an adhesion energy of 85 J m −2 on Cu, which is 13 times greater than that of graphene. This exceptional adhesion is attributed to the formation of covalent‐like Cu─C bonds while preserving its sp 2 structure, as evidenced by X‐ray photoelectron spectroscopy (XPS) and near‐edge X‐ray absorption fine structure (NEXAFS) spectroscopy. Density functional theory (DFT) calculations further elucidate that the corrugated structure of MAC facilitates the hybridization of C 2p z orbitals with Cu 4s and 3dz 2 orbitals, promoting strong bonding. These insights indicate that the amorphous structure of MAC significantly enhances adhesion while preserving its elemental composition, providing a pathway to improve the mechanical reliability and performance of two‐dimensional (2D) materials on metal substrates in various technological applications.