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The atomic-thick anticorrosion coating for copper (Cu) electrodes is essential for the miniaturisation in the semiconductor industry. Graphene has long been expected to be the ultimate anticorrosion material, however, its real anticorrosion performance is still under great controversy. Specifically, strong electronic couplings can limit the interfacial diffusion of corrosive molecules, whereas they can also promote the surficial galvanic corrosion. Here, we report the enhanced anticorrosion for Cu simply via a bilayer graphene coating, which provides protection for more than 5 years at room temperature and 1000 h at 200 °C. Such excellent anticorrosion is attributed to a nontrivial Janus-doping effect in bilayer graphene, where the heavily doped bottom layer forms a strong interaction with Cu to limit the interfacial diffusion, while the nearly charge neutral top layer behaves inertly to alleviate the galvanic corrosion. Our study will likely expand the application scenarios of Cu under various extreme operating conditions. Atomically thick anticorrosion coatings on Cu are desired for future applications, but still at its infancy. Here, the authors report a Janus-doping mechanism in bilayer graphene on Cu substrate that results in an enhanced anticorrosion performance. [ABSTRACT FROM AUTHOR]

Graphene with unique linear band structure and enhanced electron–electron interaction exhibits peculiar hot‐carrier generation. The thermalized hot carriers in graphene have potential to achieve high energy which is well above energy of the incident photons. Together with its outstanding optical and electrical properties, the exotic thermalization of hot carriers makes graphene a promising material for applications in optical up‐conversion devices and ultrafast photonics. However, the excitation efficiency of hot carriers is limited by its weak absorption and atomically thin light–matter interaction length. Here, the efficient hot‐carrier amplification is demonstrated in graphene by adjacent quantum dots (QD). With pump–probe experiments, this hot carrier amplification is found to stem from the charge collection of the two‐photon excited hot carriers in QD. Taking advantages of strong absorption of QD, the hot‐carrier excitation efficiency of graphene can be efficiently improved under near‐infrared sub‐bandgap excitation of QD. The transferred hot carriers are with energy higher than those originally excited in graphene, leading to raised hot‐carrier temperature and enhanced hot‐carrier up‐conversion. This research demonstrates QD's immense potential to realize high efficiency hot‐carrier injection in graphene‐based devices, which will promote their ability for hot‐carrier‐driven devices, optical up‐conversion devices and high‐frequency optoelectronics. [ABSTRACT FROM AUTHOR]

We report an efficient and economical way for mass production of large-scale graphene films with high quality and uniformity. By using the designed scrolled copper-graphite structure, a continuous graphene film with typical area of 200 × 39 cm2 could be obtained in 15 min, and the production rate of the graphene film and space utilization rate of the CVD reactor can reach 520 cm2⋅min−1 and 0.38 cm−1⋅min−1, respectively. Our method provides a guidance for the industrial production of graphene films, and may also accelerate its large-scale applications. [ABSTRACT FROM AUTHOR]