Yang Mingming, Wang Longlong, Qiao Xiaofen, Liu Yi, Liu Yufan, Shi Yafang, Wu Hongli, Liang Baolai, Li Xiaoli, Zhao Xiaohui
Hebei Key Laboratory of Optic-electronic Information and Materials, College of Physics Science & Technology, Hebei University, Baoding, 071002, People's Republic of China.
State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, People's Republic of China.
Nanoscale Res Lett. 2020 Sep 30;15(1):189. doi: 10.1186/s11671-020-03414-w.
The defects into the hexagonal network of a sp-hybridized carbon atom have been demonstrated to have a significant influence on intrinsic properties of graphene systems. In this paper, we presented a study of temperature-dependent Raman spectra of G peak and D' band at low temperatures from 78 to 318 K in defective monolayer to few-layer graphene induced by ion C+ bombardment under the determination of vacancy uniformity. Defects lead to the increase of the negative temperature coefficient of G peak, with a value almost identical to that of D' band. However, the variation of frequency and linewidth of G peak with layer number is contrary to D' band. It derives from the related electron-phonon interaction in G and D' phonon in the disorder-induced Raman scattering process. Our results are helpful to understand the mechanism of temperature-dependent phonons in graphene-based materials and provide valuable information on thermal properties of defects for the application of graphene-based devices.
已证明，sp杂化碳原子融入六边形网络所产生的缺陷会对石墨烯系统的本征特性产生重大影响。在本文中，我们在确定空位均匀性的情况下，对离子C+轰击诱导的缺陷单层至少层石墨烯在78至318 K低温下G峰和D'带的温度相关拉曼光谱进行了研究。缺陷导致G峰的负温度系数增加，其值与D'带几乎相同。然而，G峰的频率和线宽随层数的变化与D'带相反。这源于无序诱导拉曼散射过程中G和D'声子相关的电子 - 声子相互作用。我们的结果有助于理解基于石墨烯材料中温度相关声子的机制，并为基于石墨烯器件的应用提供有关缺陷热性质的有价值信息。
