美国哥伦比亚大学Hone, James团队报道了无氧化学气相沉积法合成可再生石墨烯。相关研究成果发表在2024年5月29日出版的《自然》。

自首次演示该工艺以来，石墨烯在铜上的化学气相沉积（CVD）合成已被广泛采用。然而，CVD生长的石墨烯在基础科学和应用中的广泛使用受到了可复制性和质量方面的挑战的阻碍。

该文中，研究人员确定微量氧是决定低压CVD生长的石墨烯的生长轨迹和质量的关键因素。无氧化学气相沉积（OF-CVD）合成快速且高度可重复，动力学可以用紧凑的模型描述，而添加微量氧会导致成核抑制和生长缓慢/不完全。通过表面污染、拉曼D峰的出现和电导率的降低来评估氧气对石墨烯质量的影响。在无氧条件下生长的外延石墨烯是无污染的，并且没有显示出可检测的D峰。经过干转移和氮化硼封装后，它显示出接近剥离石墨烯的室温电传输行为。石墨门控器件显示出发达的整数和分数量子霍尔效应。

通过强调消除痕量氧的重要性，该项工作为未来CVD系统的设计和操作提供了指导。OF-CVD合成所提供的再现性和质量的提高，将广泛影响石墨烯的基础研究和应用。

附：英文原文

Title: Reproducible graphene synthesis by oxygen-free chemical vapour deposition

Author: Amontree, Jacob, Yan, Xingzhou, DiMarco, Christopher S., Levesque, Pierre L., Adel, Tehseen, Pack, Jordan, Holbrook, Madisen, Cupo, Christian, Wang, Zhiying, Sun, Dihao, Biacchi, Adam J., Wilson-Stokes, Charlezetta E., Watanabe, Kenji, Taniguchi, Takashi, Dean, Cory R., Hight Walker, Angela R., Barmak, Katayun, Martel, Richard, Hone, James

Issue&Volume: 2024-05-29

Abstract: Chemical vapour deposition (CVD) synthesis of graphene on copper has been broadly adopted since the first demonstration of this process1. However, widespread use of CVD-grown graphene for basic science and applications has been hindered by challenges with reproducibility2 and quality3. Here we identify trace oxygen as a key factor determining the growth trajectory and quality for graphene grown by low-pressure CVD. Oxygen-free chemical vapour deposition (OF-CVD) synthesis is fast and highly reproducible, with kinetics that can be described by a compact model, whereas adding trace oxygen leads to suppressed nucleation and slower/incomplete growth. Oxygen affects graphene quality as assessed by surface contamination, emergence of the Raman D peak and decrease in electrical conductivity. Epitaxial graphene grown in oxygen-free conditions is contamination-free and shows no detectable D peak. After dry transfer and boron nitride encapsulation, it shows room-temperature electrical-transport behaviour close to that of exfoliated graphene. A graphite-gated device shows well-developed integer and fractional quantum Hall effects. By highlighting the importance of eliminating trace oxygen, this work provides guidance for future CVD system design and operation. The increased reproducibility and quality afforded by OF-CVD synthesis will broadly influence basic research and applications of graphene.

DOI: 10.1038/s41586-024-07454-5

Source: https://www.nature.com/articles/s41586-024-07454-5