地下碳分布和石墨烯-催化剂相互作用的相互依赖性
Robert S Weatherup1, Hakim Amara, Raoul Blume
1Department of Engineering, University of Cambridge , Cambridge CB3 0FA, United Kingdom.
Journal of the American Chemical Society
|September 5, 2014
概括
由于在低压下强烈的相互作用, (Ni(111) 上的石墨烯生长自我限制. 增加的碳化合物压力削弱了这种相互作用,使多层石墨烯形成并影响碳纳米管的生长.
科学领域:
- 材料科学 材料科学 材料科学
- 表面科学是一门学科.
- 纳米技术纳米技术
背景情况:
- 通过化学蒸汽沉积 (CVD) 合成石墨烯对于电子应用至关重要.
- 了解石墨烯-催化剂相互作用是控制生长的关键.
- (Ni) 是石墨烯CVD的常见催化剂.
研究的目的:
- 研究心血管疾病期间石墨烯-催化剂相互作用的动态.
- 阐明碳分布与相互作用强度之间的关系.
- 提供关于自我限制生长和多层形成的见解.
主要方法:
- 在现场,时间和深度分辨率的X射线光电子光谱 (XPS).
- 大法典蒙特卡洛 (GCMC) 模拟.
- 紧密结合 (TB) 模型.
主要成果:
- 强烈的石墨烯-Ni(111) 相互作用消耗了近表面的碳,导致低压 (10−610−3 mbar) 的自我限制生长.
- 增加的碳化合物压力 (∼10−1 mbar) 会削弱相互作用,通过增加近表面碳,促进多层石墨烯.
- 弱粘附,旋转的石墨烯生长与更高的初始近表面碳水平相关.
结论:
- 在Ni(111) 上的石墨烯生长动态是由相互作用强度和近表面碳度之间的相互作用决定的.
- 结果为石墨烯合成提供了控制策略.
- 这些发现对于理解碳纳米管生长机制具有重要意义.
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