Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 37673, South Korea.
National Institute for Nanomaterials Technology, Pohang University of Science and Technology, Pohang, 37673, South Korea.
Adv Mater. 2017 Aug;29(32). doi: 10.1002/adma.201700753. Epub 2017 Jun 21.
The synthesis of Bernal-stacked multilayer graphene over large areas is intensively investigated due to the value of this material's tunable electronic structure, which makes it promising for use in a wide range of optoelectronic applications. Multilayer graphene is typically formed via chemical vapor deposition onto a metal catalyst, such as Ni, a Cu-Ni alloy, or a Cu pocket. These methods, however, require sophisticated control over the process parameters, which limits the process reproducibility and reliability. Here, a new synthetic method for the facile growth of large-area Bernal-stacked multilayer graphene with precise layer control is proposed. A thin Ni film is deposited onto the back side of a Cu foil to induce controlled diffusion of carbon atoms through bulk Cu from the back to the front. The resulting multilayer graphene exhibits a 97% uniformity and a sheet resistance of 50 Ω sq with a 90% transmittance after doping. The growth mechanism is elucidated and a generalized kinetic model is developed to describe Bernal-stacked multilayer graphene growth by the carbon atoms diffused through bulk Cu.
由于这种材料可调谐的电子结构具有很高的价值，使其在各种光电应用中具有广阔的应用前景，因此人们正在积极研究大面积的伯纳尔堆叠多层石墨烯的合成。通常通过化学气相沉积在金属催化剂（如 Ni、Cu-Ni 合金或 Cu 口袋）上形成多层石墨烯。然而，这些方法需要对工艺参数进行复杂的控制，这限制了工艺的可重复性和可靠性。在这里，提出了一种新的简便合成大面积伯纳尔堆叠多层石墨烯的方法，具有精确的层控制。在 Cu 箔的背面沉积一层薄的 Ni 膜，以诱导碳原子通过大块 Cu 从背面到正面的受控扩散。所得多层石墨烯的均匀性为 97%，掺杂后的方阻为 50 Ω/sq，透光率为 90%。阐明了生长机理，并开发了一个广义的动力学模型来描述通过大块 Cu 扩散的碳原子生长伯纳尔堆叠多层石墨烯。
